{"paper_id":"3c04e79d-6ebe-401d-af69-ceb40fd9d4e8","body_text":"Association between hospital volume and mortality after elective oesophageal cancer resection in Switzerland: A retrospective national registry study from 2013 to 2022 | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Association between hospital volume and mortality after elective oesophageal cancer resection in Switzerland: A retrospective national registry study from 2013 to 2022 Yanic Ammann, Rene Warschkow, Marie Klein, Kristjan Ukegjini, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8707208/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 7 You are reading this latest preprint version Abstract Purpose: The association between a high annual hospital-specific case volume and improved postoperative outcomes after oesophageal cancer resection (OCR) is well described. The Swiss government started centralisation of OCR in 2013. This study investigates this centralisation in terms of the annual hospital-specific case volume of OCR (hospital volume) and its effect on short-term postoperative outcomes. Methods: National inpatient registry data of all hospitals providing OCR (ICD codes C15 and at least one of the CHOP codes starting with 424, 425, or 426) between 2013 and 2022 in Switzerland were analysed. The primary endpoint was in-hospital mortality. Secondar endpoints were postoperative complications and length of hospital stay (LOS). Additional objectives were sociodemographic time trends. Results: 1’535 cases were identified. The annual number of hospitals providing OCR ranged between 30 in 2013 and 14 in 2021. Hospital volume varied between one and 40 patients per year. Overall mortality was 5.3% (n=81) declining from 9.3% in 2013 to 3.8% in 2022 (t=-0.511, p=0.040). Increasing hospital volume was associated with lower risk for mortality (odds ratio (OR)=0.723, 95% confidence interval (CI) 0.53 to 0.98, p=0.037) and postoperative complications (OR=0.705, 95%CI: 0.62 to 0.83, p<0.001), and shorter LOS from the 8th quantile of LOS upwards (p<0.001). Conclusions: A higher hospital volume is associated with reduced mortality and postoperative complications. The ongoing centralisation of OCR in Switzerland must be further advanced in order to enhance clinical outcomes, ensure patient safety, and be able to compare nationally with international benchmark centres. Clinical trial registration ClinicalTrials.gov, NCT07022652, https://clinicaltrials.gov/search?id=NCT07022652 Oesophageal cancer surgery hospital volume mortality postoperative complications Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 What does this paper add to the literature ? This retrospective Swiss national registry study between 2013 and 2022 confirms the association between an increasing annual-hospital specific case volume of oesophageal cancer resection and improved short-term postoperative outcomes. Furthermore, the necessity of further centralisation of this highly complex procedure in Switzerland is demonstrated in order to achieve the outcome of international benchmark centres. Introduction The effect of centralisation on postoperative outcomes after oesophageal cancer resection (OCR) in Switzerland has not been highlighted yet. Oesophageal cancer is a rare malignancy in Switzerland. It accounts for only 2% of all cancers, with an annual incidence of 603 cases between 2017 and 2021.[1] The prognosis of oesophageal cancer is poor. The 437 annual oesophageal cancer-related deaths between 2017 and 2021 resulted in a low 5-year overall survival of only 30%.[2] The therapeutic management of oesophageal cancer (neoadjuvant therapy, interventional therapy, surgical technique, adjuvant therapy) was driven by innovation and changed considerably in recent years, resulting in a complex therapy algorithm.[3-7] Together with the often polymorbid patients, the very demanding surgical technique, and the challenges in postoperative management, a specialised, high-volume, interdisciplinary treatment team is required.[8, 9] The centralisation of such complex surgical procedures in specialised centres aims to build up such treatment teams, resulting in improved quality of the treatment and increased patient safety.[10] The association between a high annual hospital-specific case load of OCR (hospital volume) and improved short-term postoperative outcomes as well as long-term survival has been well documented in current scientific literature.[11, 12] International benchmark centres suggest a threshold between 20 and 40 for high-volume centres.[13, 14] A threshold value of 12 was introduced for the first time in 2013 in Switzerland.[15] The threshold and other regulations resulted in only eight hospitals with a performance mandate for OCR.[16] Previously, 69 hospitals performed OCR in Switzerland, and the in-hospital mortality of 5.9% was significantly higher compared to international benchmark centres from ESODATA (2.0%) or DUCA (2.5% to 4.4%).[13, 14, 17-19] This retrospective registry study provides Swiss national data on short-term postoperative outcomes after elective OCR in Switzerland from 2013 to 2022. It aims to examine the effect of the ongoing centralisation through the association between the hospital volume and in-hospital mortality, postoperative complications, and length of hospital stay (LOS). Materials and Methods Study design This is a retrospective population-based analysis from the Swiss national inpatient registry between 2013 and 2022. The anonymised data was obtained from the Swiss Federal Statistics Office (FSO) via a data contract for the one-time delivery and use of individual data (without personal identification) in Switzerland. At the time of ordering the data in 2024, the data from 2023 was not yet available. The data contained detailed information from all Swiss hospitals’ inpatient cases between 2013 and 2022 as described in the supplementary material. Case selection The cases were selected according to their “International Statistical Classification of Diseases and Related Health Problems 10 th Revision” (ICD) and “Swiss Classification of Operations” (CHOP) codes.[20, 21] A case was selected for OCR when at least one of the ICD codes started with C15 (malignant neoplasm of the oesophagus [oesophageal cancer] and at least one of the CHOP codes started with 42.4 (excision of the oesophagus), 42.5 (intrathoracic anastomosis on the oesophagus), or 42.6 (in front of the sternum oesophagostomy). Exclusion criteria included emergency admission, incomplete case documentation, age under 20 years, and hospitalisation in non-general or non-surgical hospitals. Incomplete documentation occurs due to the strictly full calendar year (from 1 st January to 31 st December) based classification of the FSO. Data from patients hospitalised overnight on the 31 st of December are therefore incomplete.[17] The inclusion of 18- and 19-year-olds was not possible due to the data structure with five-year age groups. Other hospitals than general and surgical hospitals were excluded because of the low levels of comorbidities and the relatively low risk of dying in the hospital.[22] Primary and secondary endpoints The primary endpoint of this study was postoperative mortality, defined as in-hospital mortality. Secondary endpoints were postoperative complications and length of hospital stay (LOS). The analysed postoperative complications comply with ESODATA specifications and are shown in Table 3.[13] Additional objectives were sociodemographic trends (number of operations, number of hospitals providing the operation, mean hospital volume, age, Charlson comorbidity index (CCI), sex, intensive care unit (ICU) stay, nationality, insurance, robotic access (CHOP code 00.99.50)) between 2013 and 2022.[23] The CCI and ICU stay were assumed as described in the supplementary material. Statistical analysis The R statistical software was used for statistical analysis (www.r-project.org). A two-sided p-value of less than 0.05 was considered statistically significant. Continuous data were expressed as the mean with standard deviation (SD), interquartile range (IQR) and the range. In descriptive analysis, proportions were compared with the chi-square statistics, and continuous variables were compared with t tests and Mann‒Whitney U tests, as appropriate. The associations between the hospital volume and mortality and postoperative complications were assessed by generalized additive regression models (GAM) adjusting for year of operation with random effect B-splines. The confounding variable set included sex (male vs. female), age (continuous), CCI (continuous), nationality (foreign vs. Swiss), insurance (general vs. private (semi-private and private)), hospital type (university vs. tertiary vs. other (basic hospitals and specialised surgical hospitals)). Results were additionally presented graphically with an easy-to-interpret marginal effect analysis as described in the supplementary material.[24, 25]. For the LOS, an ordinary least square regression was complemented by an in-depth analysis by quantile regression analysis to assess the associations between the hospital volume and the different lengths of the LOS, not disturbed by outliers or skewed data, as described in the supplementary material.[26] The time trends were assessed using the nonparametric Mann-Kendall trend test from the R trend library.[27] Its value is between -1 (perfect descending trend) and +1 (perfect ascending trend) with 0 representing no trend at all.[28] Ethics This study was approved by the Ethics Committee of Eastern Switzerland (BASEC B2025-00702), registered under ClinicalTrials.gov (NCT07022652), and is compliant with the Strengthening the Reporting of Observation in Epidemiology (STROBE) guidelines.[29] It conforms to the provisions of the Declaration of Helsinki. There were no deviations from the published protocol. Results Case selection The dataset provided by the FSO contained data of 14’438’938 cases. 22’837 cases had an oesophageal cancer diagnosis. 1’595 cases had an OCR. Fifty-nine cases were excluded due to emergency admission, and one case was excluded due to incomplete case documentation. 1’535 cases were included in the analysis (Fig.1). Case baseline characteristics The case baseline characteristics are shown in Table 1. The OCRs were predominantly performed at university and tertiary hospitals (39.4% and 57.4%) on men (78.4%) with a mean age of 64.7 years. Only 23.4% of the cases were treated at institutions with a hospital volume exceeding 18 cases (Fig.2). Mortality Overall mortality was 5.3% (n=81). A higher hospital volume was associated with 27.7% lower odds for mortality for every ten additional cases (odds ratio (OR)=0.723, 95% confidence interval (CI) 0.534 to 0.981, p=0.037) (Fig.3). According to the GAM logistic regression, higher age (OR=1.028, 95%CI 1.002 to 1.055, p=0.033) and higher CCI (OR=1.218, 95%CI 1.095 to 1.355, p<0.001) had higher odds for mortality. Year of operation was a significant random effect (p=0.013) (Table 2). Postoperative complications The complications are shown in Table 3. The overall complication rate was 69.3% (n=1’063). A higher hospital volume was associated with 29.5% lower odds for overall complications for every ten additional cases (OR=0.705, 95%CI 0.608 to 0.816, p<0.001) (Fig.4). According to the GAM logistic regression, higher age (OR=1.022, 95%CI 1.010 to 1.034, p<0.001) had higher odds while tertiary hospitals (OR=0.749, 95%CI 0.572 to 0.980, p=0.035) had lower odds for overall complications (Table 4). The overall anastomotic leakage rate between 2015 and 2022 was 20.7% (n=241). A higher hospital volume was not associated with lower odds for anastomotic leakage (OR=0.861, 95%CI 0.682 to 1.086, p=0.207). However, the occurrence of anastomotic leakage was strongly associated with mortality (OR 3.758, 95%CI 1.614 to 8.753, p=0.002). The associations between all other complications and hospital volume and mortality are shown in the supplementary material table SM1. Length of hospital stay The mean LOS was 24.8 days (SD 18.5). In ordinary regression, no association between LOS and hospital volume was observed (β=0.007, 95%CI -0.093 to 0.108, p=0.889). In-depth quantile regression showed a heterogenous effect with estimates becoming increasingly negative at the higher quantiles 0.8 and 0.9 (joint p<0.001) (Figure 5). However, no significant effect was evident on quantile-specific level (Table 5). Trend analysis between 2013 and 2022 Trend analysis is shown in table 6. The annual number of hospitals providing OCR decrease from 30 in 2013 to 18 in 2022 (tau=-0.750, p=0.003) with its lowest number of 14 hospitals in 2021. The number of annual OCR also decreased from 183 in 2013 to 133 in 2022 (tau -0.733, p=0.003) with its lowest number of 121 in 2020. This resulted in a steady mean hospital volume between 6.1 in 2013 and 7.4 in 2022 (t=0.244, p=0.325). Further significant trends over time were evident for ICU stay (tau=-0.822, p<0.001), private insurance (tau=-0.511, p=0.040), and robotic access (tau=+0.809, p=0.001) (Table 6). Discussion The present retrospective Swiss national registry study is the first to examine the effect of centralisation of OCR on hospital volume and short-term postoperative outcomes in Switzerland. Cases operated at institutions with higher hospital volume had lower mortality and lower postoperative complications. A higher hospital volume was associated with lower mortality of nearly 28% for every ten additional cases. This finding aligns with other studies investigating the association between hospital volume and postoperative outcomes in OCR. US-American, UK, German, Japanese, and Korean national registry studies have described a similar association between hospital volume and postoperative mortality.[30-35] Their study populations ranged from 4’868 to 28’931 cases, and the periods examined spanned from three to 15 years between 1998 and 2017. Most analyses did not compare hospital volume as a marginal effect. Hospitals were divided into three groups: low-volume (threshold between 5 to 12 cases), mid-, and high-volume (threshold between 19 to 48 cases). These findings were confirmed in a recent meta-analysis, which showed a significantly reduced relative risk of postoperative mortality by 53% in high-volume hospitals compared to low-volume hospitals (threshold 45 cases, OR=0.47, 95%CI 0.42 to 0.53).[11] Overall, the mortality of 5.3% was higher compared to the international benchmark centres from ESODATA (2.0%) or DUCA (2.5% to 4.4).[13, 14] After starting centralisation in 2013, the annual mortality rate was significantly reduced (tau=-0.511, p=0.040) between 2013 (9.3%) and 2022 (3.8%). The lowest annual mortality rate of 2.0% in 2018 can keep up with these international benchmark centres. A higher hospital volume was associated with lower postoperative complications of nearly 30% for every ten additional cases. Studies investigating the association between hospital volume and overall complications as a primary outcome are sparse. Most studies focus on mortality. The complete assessment of postoperative complications from large registries can be challenging. A nationwide analysis of 29’116 patients between 2016 and 2020 from the United States focusing on minimal invasive oesophagectomy described lower odds for major complications (OR=0.83, 95%CI 0.70 to 0.96, p=0.05) in hospital with a hospital volume >16.[36] DUCA showed less technical complications (OR=0.82, 95%CI 0.70 to 0.96), less anastomotic leakage (OR=0.80, 95%CI 0.66 to 0.97), and more textbook outcome (OR=1.25, 95%Cl 1.07 to 1.46) in hospitals with hospital volume >39.[37] A recent meta-analysis of 177’566 patients also showed a lower leak rate in hospitals with hospital volume >36 (9.6% vs. 8.3%, p=0.040). Meta-regression confirmed an association between annual oesophagectomies per centre and anastomotic leakage (β=-0.0008, SD 0.0003, p=0.0183).[38] One possible explanation for the difference to our results regarding anastomotic leakage could be the generally higher hospital volume and threshold in these studies. The overall complication rate (69.3%) and the rate of anastomotic leakage (20.7%) were just slightly higher compared to ESODATA (60.5% and 12.5%) and DUCA (56.8% to 66.4% and 18.2% to 19.3%).[13, 14] The extent to which the high-resource setting of the highly developed Swiss health care system can compensate for this remains unclear in this study. The current Swiss hospital volume threshold of 12 was set in 2013 and confirmed in the first revision in 2019.[15, 16] This is significantly below the threshold for high-volume centres proposed by ESODATA (n=40 to 50), DUCA (n=20), or the German S3 guideline (n=20).[3, 13, 14] The observation that the mean hospital volume remained stable despite a reduction in the number of hospitals and number of OCR performed per year does not fully support an effect of centralisation. The reduction of surgeries between 2013 and 2022 was somewhat astonishing. Normally, as a database becomes well established, the number of surgeries increases.[39] The current national registry went in the opposite direction. There are various possible explanations. The incidence of oesophageal cancer in Switzerland decreased in the study period.[40] A more profound prevention and screening may result in an increase in detection of early-stage cases with possible endoscopic therapy. Definitive radiochemotherapy has established itself as an alternative for squamous cell carcinomas and multimorbid patients.[3] Centralisation of highly complex surgery with high perioperative risk can result in stricter case selection.[41] At least, the COVID-19 pandemic could also have contributed to a reduced number of OCR.[42] Despite the decrease in number of hospitals performing OCR, a significant proportion of the data reported in this study came from low- to mid-volume, high-resource centres, as defined by international standards. As the perioperative management of OCR is very challenging, focusing on high-volume institutions alone is not advisable. A highly competent, dedicated, and resilient surgeon must rely on an interdisciplinary team of intensive care physicians (84.6% of cases involved an ICU stay), gastroenterologists, interventional radiologists, nutrition professionals, nursing professionals, and other relevant disciplines.[43-47] Optimal outcomes rely on the synergy of a well-coordinated interdisciplinary team and a skilled surgeon with excellent intraoperative decision-making. A high hospital volume increases clinical expertise and strengthens multidisciplinary teamwork. This leads to improved patient outcomes, as demonstrated by the results of our study. The data from this study, the studies mentioned above, and the international benchmark centres should be considered in the next allocation review for OCR in Switzerland, which started in July 2025. The authors suggest an upward adjustment of the threshold value. Strengths and limitations The strengths of this study are the high case number, the high external validity through presentation of real-world data, the national population-based coverage minimalizing selection bias, and the minimal costs per case using government-collected data. There are some limitations next to the low- to mid-volume, high-resource setting mentioned above. Non-randomized studies only allow associations to be made, not causal statements. They carry a relevant risk of confounding by indication, time-related biases (changes in surgical, medical, and intensive care treatment) and bias from unobserved variables. The data used in this analysis were not primarily collected for research purposes and do not contain detailed clinical variables and depth. Due to the absence of the American Society of Anesthesiologists Physical Status classification, multimodal treatment strategy, surgical approach, operative details, histology, and the Clavien-Dindo classification of postoperative complications, several important patient characteristics are missing, as they are not reported in the FSO data. The transformation of clinical data into registry codes and back into clinical data makes such registry studies prone to reporting bias due to miscoding, underreporting, and incomplete documentation.[48] The effect of centralisation, whereby sicker patients are more likely to be operated on at hospitals with higher case numbers, can lead to distortions.[35, 49] Conclusion A higher hospital volume is associated with reduced mortality and postoperative complications. The ongoing centralisation of OCR in Switzerland must be further advanced in order to enhance clinical outcomes, ensure patient safety, and be able to compare nationally with international benchmark centres. Declarations Authors’ contribution statement Yanic Ammann Conceptualisation, data curation, investigation, methodology, visualisation, writing - original draft Rene Warschkow Conceptualisation, data curation, formal analysis, software, validation, visualisation, writing – review & editing Marie Klein Writing – review & editing Kristjan Ukegjini Writing – review & editing Ignazio Tarantino Writing – review & editing Thomas Steffen Conceptualisation, resources, project administration, supervision, writing – original draft, review & editing Funding statement Thomas Steffen holds a grant from the “Stiftung Chirurgie”, St.Gallen, Switzerland, to financially support young researchers in translation, manuscript editing, and publication costs. Conflict of interest disclosure None of the authors has any conflicts of interest to disclose. Patient consent statement The data was obtained anonymously from the Swiss Federal Statistics Office (FSO) via a data contract for the one-time delivery and use of individual data (without personal identification) in Switzerland. Ethics approval statement This study was approved by the Ethics Committee of Eastern Switzerland (BASEC B2025-00702), registered under ClinicalTrials.gov (NCT07022652), and is compliant with the Strengthening the Reporting of Observation in Epidemiology (STROBE) guidelines. It conforms to the provisions of the Declaration of Helsinki. Consent for publication This submission is to Langenbeck's Archives of Surgery. The material is original research, has not been previously published, and has not been submitted for publication elsewhere while under consideration. Data availability / sharing statement The anonymised case data supporting this study's findings can be obtained from the Swiss Federal Statistics Office (FSO). Acknowledgments To medical coding expert Dr. Therese Kim for helping with the data processing. References Krebsregistrierungsstelle BfSN. Krebs, Neuerkrankungen und Sterbefälle: Anzahl, Raten, Medianalter und Risiko pro Krebsart 2024 [Available from: https://www.bfs.admin.ch/bfs/de/home/statistiken/gesundheit/gesundheitszustand/krankheiten/krebs/daten.assetdetail.33250863.html. Krebsliga-Schweiz. Krebs in der Schweiz: wichtige Zahlen. 2024. AWMF. S3-Leitlinie Diagnostik und Therapie der Plattenepithelkarzinome und Adenokarzinome des Ösophagus 2023 [Available from: https://register.awmf.org/de/leitlinien/detail/021-023OL. Kato H, Nakajima M. Treatments for esophageal cancer: a review. Gen Thorac Cardiovasc Surg. 2013;61(6):330-5. Lewis S, Lukovic J. Neoadjuvant Therapy in Esophageal Cancer. Thorac Surg Clin. 2022;32(4):447-56. 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Overall Volume Trends in Esophageal Cancer Surgery Results From the Dutch Upper Gastrointestinal Cancer Audit. Ann Surg. 2021;274(3):449-58. Rahouma M, Baudo M, Mynard N, Kamel M, Khan FM, Shmushkevich S, et al. Volume outcome relationship in postesophagectomy leak: a systematic review and meta-analysis. Int J Surg. 2024;110(4):2349-54. Alluri RK, Leland H, Heckmann N. Surgical research using national databases. Ann Transl Med. 2016;4(20):393. Bundesamt-für-Statistik. Krebsmonitoring Schweiz, Speiseröhrenkrebs ICD-10 C15 2025 [Available from: https://krebs-monitoring.bfs.admin.ch/de/detail/C15. Ramsay AI, Tomini SM, Gandhi S, Fulop NJ, Morris S. Centralisation of specialised healthcare services: a scoping review of definitions, types, and impact on outcomes. Health Soc Care Deliv Res. 2025:1-70. Milito P, Asti E, Resta M, Bonavina L. Minimally invasive esophagectomy for cancer in COVID hospitals and oncological hubs: are the outcomes different? Eur Surg. 2022;54(2):98-103. 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High-quality nursing can reduce the incidence of adverse events in esophageal cancer patients after operation in the intensive care unit and improve postoperative rehabilitation. Am J Transl Res. 2021;13(10):11851-9. Lucyk K, Tang K, Quan H. Barriers to data quality resulting from the process of coding health information to administrative data: a qualitative study. BMC Health Services Research. 2017;17(1):766. Munir MM, Woldesenbet S, Endo Y, Dillhoff M, Tsai S, Pawlik TM. Association of Hospital Market Competition with Outcomes of Complex Cancer Surgery. Ann Surg Oncol. 2024;31(7):4371-80. Tables Table 1 Case baseline characteristics Variable Label Total n=1’535 Age (years) Mean (SD) 64.7 (9.7) Range 22.0-87.0 Sex Male 1203 (78.4%) Female 332 (21.6%) Nationality Foreign 177 (11.5%) Swiss 1358 (88.5%) Insurance General 1060 (69.1%) Private 475 (30.9%) CCI Mean (SD) 3.8 (2.0) Range 2.0-11.0 UICC stage I/II 1024 (66.7%) III 457 (29.8%) IV 54 (3.5%) Type of hospital University 605 (39.4%) Tertiary 881 (57.4%) Other 49 (3.2%) Hospital volume Mean (SD) 13.7 (9.2) Range 1.0-40.0 > 12.0 (50th percentile) 648 (42.2%) > 18.0 (75th percentile) 359 (23.4%) > 26.0 (90th percentile) 141 (9.2%) Robotic access Yes 113 (7.4%) ICU stay Yes 1350 (87.9%) Hours on ICU Mean (SD) 145.8 (260.8) Range 3.0-5026.0 SD: Standard deviation; CCI: Charlson comorbidity index; UICC: Union Internationale Contre le Cancer; ICU: Intensive care unit Table 2 GAM logistic regression for mortality Variable Label OR 95%CI p-value Hospital volume continuous 0.723 0.534 to 0.981 0.037 Age continuous 1.028 1.002 to 1.055 0.033 Sex Male reference - - Female 0.973 0.557 to 1.701 0.924 CCI continuous 1.218 1.095 to 1.355 <0.001 Nationality Foreign reference - - Swiss 0.917 0.439 to 1.915 0.817 Insurance General reference - - Private 0.865 0.521 to 1.436 0.575 Type of hospital University reference - - Tertiary 0.833 0.487 to 1.425 0.504 Other 0.752 0.196 to 2.890 0.678 Year of operation Random effect - - 0.013 Significant values are bold OR: Odds ratio; CI: Confidence interval; CCI: Charlson comorbidity index Table 3 Complications Variable Label Total n=1’535 Complications overall Yes 1063 (69.3%) Reoperation° 00.99.10 136 (8.9%) Myocardial infarction* I21, I22 5 (0.3%) Cardiac arrest* I46 22 (1.4%) Arterial fibrillation* I48 353 (23.0%) DVT and PE* I26.0, I26.9, I80.2 58 (3.8%) Pneumonia* J13-18, J85.1 243 (15.8%) Pleural effusion* J90, J91 368 (24.0%) Pleural empyema* J86.0, J86.9 112 (7.3%) Aspiration* J69.0, J69.8, J95.4 124 (8.1%) Atelectasis* J98.1 137 (8.9%) Mediastinitis* J85.3, J98.5 66 (4.3%) Pneumothorax* J93, J95.80, S27.0 166 (10.8%) Haemothorax* J94.2, S27.1, S27.2 9 (0.6%) Pulmonal insufficiency, respiratory failure* J95.1, J95.2, J95.3, J96 237 (15.4%) ARDS* J80 37 (2.4%) Acute kidney injury* N17, N19 116 (7.6%) Urinary tract infection* N10, N30.0, N30.9, N39.0 52 (3.4%) Urinary retention* R33 41 (2.7%) Anastomotic leakage * n/a 2013 and 2014 368 (24.0%) No 2015 to 2022 926 (79.3%)ꜝ K91.83 2015 to 2022 241 (20.7%)ꜝ Anastomotic stenosis* K22.2 69 (4.5%) Gastrointestinal ulcer* K25, K28 29 (1.9%) Peritonitis and intraabdominal abscess* K65 20 (1.3%) Delayed gastric emptying* K31.88 50 (3.3%) Ileus* K56, K91.3 55 (3.6%) Bleeding* T81.0, S36.81 88 (5.7%) Shock* T81.1 5 (0.3%) Lymphatic fistula* I89.8, J94.0 58 (3.8%) Wound dehiscence* T81.3 64 (4.2%) SSI* T81.4, T89.02, L08.9 108 (7.0%) Other vascular complication* T81.7 1 (0.1%) Injury to the heart* S26.0 2 (0.1%) Injury to the lungs or pleura* S27.0, S21.3, S27.6 39 (2.5%) Tracheobronchial injury* S27.4, S27.5 10 (0.7%) Injury to the thoracic duct* S27.82 5 (0.3%) Injury to the diaphragm* S27.81 2 (0.1%) Injury to other or multiple thoracal organs* S27.7, S27.83, S27.84, S27.88, S27.9 3 (0.2%) Recurrent laryngeal nerve palsy* J38, G52.2 61 (4.0%) Other intraoperative injuries* T81.2 15 (1.0%) Intraoperative retained foreign body* T81.5, T81.6 1 (0.1%) Other complications* J95.8, J95.9, K91.88, K91.9, T81.8, T81.9 200 (13.0%) °: Swiss Classification of Operations” (CHOP) codes *: International Statistical Classification of Diseases and Related Health Problems 10th Revision” (ICD) ꜝ: total operation between 2015 and 2022 n=1’167 SD: Standard deviation; DVT: Deep venous thrombosis; PE: Pulmonary embolism; ARDS: Acute respiratory distress syndrome; n/a: Not available; SSI: Surgical site infection Table 4 GAM logistic regression for overall complication Variable Label OR 95%CI p-value Hospital volume continuous 0.705 0.608 to 0.816 <0.001 Age continuous 1.022 1.010 to 1.034 <0.001 Sex Male Ref - - Female 1.283 0.972 to 1.692 0.078 CCI continuous 1.029 0.973 to 1.087 0.318 Nationality Foreign Ref - - Swiss 0.728 0.506 to 1.047 0.087 Insurance General Ref - - Private 1.164 0.905 to 1.499 0.237 Type of hospital University Ref - - Tertiary 0.749 0.572 to 0.980 0.035 Other 0.676 0.321 to 1.421 0.301 Year of operation Random effect - - 0.107 Significant values are bold OR: Odds ratio; CI: Confidence interval; CCI: Charlson comorbidity index Table 5 Quantile regression for length of hospital stay Quantile LOS (days) Coefficient of hospital volume (95% CI) 0.1 12 0.057 (-0.120 to 0.094) 0.2 14 0.000 (0.000 to 0.107) 0.3 15.2 0.056 (-0.036 to 0.093) 0.4 17 0.000 (0.000 to 0.082) 0.5 19 0.000 (0.000 to 0.083) 0.6 22 -0.028 (-0.088 to 0.160) 0.7 25 -0.000 (-0.123 to 0.074) 0.8 31 -0.065 (-0.177 to 0.081) 0.9 43 -0.182 (-0.451 to 0.100) LOS: Length of hospital stay; CI: Confidence interval Table 6 Trend analysis Variable Sum / average 2013 2022 tau trend p value* Mortality (%) 5.1 9.3 3.8 -0.511 0.040 Overall complications (%) 69.2 63.9 72.9 0.289 0.245 Number of operations 1’535 183 133 -0.733 0.003 Number of hospitals 19.9 30 18 -0.750 0.003 Mean hospital volume 7.9 6.1 7.4 0.244 0.325 Mean age (years) 64.7 64.7 66.3 0.156 0.531 Mean CCI 3.8 3.5 3.9 0.422 0.089 Women (%) 21.6 23.0 17.3 -0.156 0.531 ICU stay (%) 87.2 96.2 76.7 -0.822 <0.001 Swiss (%) 88.4 85.9 90.2 0.045 0.857 Private insurance (%) 30.3 31.7 26.3 -0.511 0.040 Robotic access (%) 8.07 0.0 23.3 0.809 0.001 Mean LOS (days) 24.8 26.7 25.5 -0.200 0.421 *Significant values are bold CCI: Charlson comorbidity index; ICU: Intensive care unit; LOS: Length of hospital stay Additional Declarations No competing interests reported. Supplementary Files Supplementarymaterial.docx TableSM1.docx Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 11 Apr, 2026 Reviews received at journal 31 Mar, 2026 Reviewers agreed at journal 31 Mar, 2026 Reviewers invited by journal 24 Mar, 2026 Editor assigned by journal 04 Feb, 2026 Submission checks completed at journal 04 Feb, 2026 First submitted to journal 27 Jan, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {\"props\":{\"pageProps\":{\"initialData\":{\"identity\":\"rs-8707208\",\"acceptedTermsAndConditions\":true,\"allowDirectSubmit\":false,\"archivedVersions\":[],\"articleType\":\"Research Article\",\"associatedPublications\":[],\"authors\":[{\"id\":611123200,\"identity\":\"578266ac-d12a-441a-bb25-12b820bf55b5\",\"order_by\":0,\"name\":\"Yanic Ammann\",\"email\":\"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA3klEQVRIiWNgGAWjYJCCA3DWxwYgIcHAwEy0FsaZxGqBA2ZeYrQYHD978MAPBrto3fazxx7b7mCQ45/dwPi5AJ+WM3kJB3sYknO3nclLN849w2AscecAs/QMfFoO5BgcBrokd9uBHDPp3Lb/iRskEtiYefBpOf8GpKU+d9v5N2bSlm0MRGi5AbblcO62G0BbGInRInnjjcHBHoPjQC1vzCR724B+uZHYLI1PC9/5HOMPPyqqgQ7LMZP42QYMsRnJBz/j06JwAOw8FDHGBjwaGBjk8UuPglEwCkbBKAACAEfMTKn0oMcPAAAAAElFTkSuQmCC\",\"orcid\":\"\",\"institution\":\"Kantonsspital St. Gallen\",\"correspondingAuthor\":true,\"prefix\":\"\",\"firstName\":\"Yanic\",\"middleName\":\"\",\"lastName\":\"Ammann\",\"suffix\":\"\"},{\"id\":611123201,\"identity\":\"27fc64d9-d31d-4164-b175-74b1e9895ee5\",\"order_by\":1,\"name\":\"Rene Warschkow\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Kantonsspital St. Gallen\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Rene\",\"middleName\":\"\",\"lastName\":\"Warschkow\",\"suffix\":\"\"},{\"id\":611123202,\"identity\":\"e46734af-a837-4085-b7dc-12e289bc0702\",\"order_by\":2,\"name\":\"Marie Klein\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Kantonsspital St. Gallen\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Marie\",\"middleName\":\"\",\"lastName\":\"Klein\",\"suffix\":\"\"},{\"id\":611123203,\"identity\":\"c80e8406-339e-4c84-831b-ef51c060eb4f\",\"order_by\":3,\"name\":\"Kristjan Ukegjini\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Kantonsspital St. Gallen\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Kristjan\",\"middleName\":\"\",\"lastName\":\"Ukegjini\",\"suffix\":\"\"},{\"id\":611123204,\"identity\":\"3a4731a9-8e2d-4532-a2cd-46f981f09203\",\"order_by\":4,\"name\":\"Ignazio Tarantino\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Kantonsspital St. Gallen\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Ignazio\",\"middleName\":\"\",\"lastName\":\"Tarantino\",\"suffix\":\"\"},{\"id\":611123205,\"identity\":\"5d407e52-b2a9-49fc-b787-6141786fefa5\",\"order_by\":5,\"name\":\"Thomas Steffen\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Kantonsspital St. Gallen\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Thomas\",\"middleName\":\"\",\"lastName\":\"Steffen\",\"suffix\":\"\"}],\"badges\":[],\"createdAt\":\"2026-01-27 07:38:48\",\"currentVersionCode\":1,\"declarations\":\"\",\"doi\":\"10.21203/rs.3.rs-8707208/v1\",\"doiUrl\":\"https://doi.org/10.21203/rs.3.rs-8707208/v1\",\"draftVersion\":[],\"editorialEvents\":[],\"editorialNote\":\"\",\"failedWorkflow\":false,\"files\":[{\"id\":105496141,\"identity\":\"fe0b8f86-268d-4b85-a4f8-799dded274ae\",\"added_by\":\"auto\",\"created_at\":\"2026-03-26 16:25:28\",\"extension\":\"png\",\"order_by\":1,\"title\":\"Figure 1\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":17241,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eCase selection\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"Fig1.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-8707208/v1/54c6fd86b614ae4fb06c2bf7.png\"},{\"id\":105496248,\"identity\":\"535be163-a04f-43c6-af9c-6ccdefae70db\",\"added_by\":\"auto\",\"created_at\":\"2026-03-26 16:25:31\",\"extension\":\"png\",\"order_by\":2,\"title\":\"Figure 2\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":16020,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eHistogram of frequency of oesophageal cancer resection according to the hospital volume. X-axis: number of annual resections per hospital in groups of five. Y-axis: frequency of observations.\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"Fig2.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-8707208/v1/fe0e4e4cca50734836551919.png\"},{\"id\":105496256,\"identity\":\"1073621f-9ef0-456c-ba07-4ee8cc86cc06\",\"added_by\":\"auto\",\"created_at\":\"2026-03-26 16:25:36\",\"extension\":\"png\",\"order_by\":3,\"title\":\"Figure 3\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":32181,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eMarginal effect analysis of hospital volume and mortality. Red line: GAM logistic regression. Red shaded area: 95% confidence interval of the GAM logistic regression.\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"Fig3.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-8707208/v1/a5ddb1c86f81784d1bcdf480.png\"},{\"id\":105496129,\"identity\":\"a8d6e97b-e14b-4e6a-8c52-5c65aa06d13f\",\"added_by\":\"auto\",\"created_at\":\"2026-03-26 16:25:26\",\"extension\":\"png\",\"order_by\":4,\"title\":\"Figure 4\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":37906,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eMarginal effect analysis of hospital volume and postoperative complications. Red line: GAM logistic regression. Red shaded area: 95% confidence interval of the GAM logistic regression.\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"Fig4.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-8707208/v1/620d98c129ee2d36d28a24e8.png\"},{\"id\":105496009,\"identity\":\"dc8c5eab-3a16-4b3f-930a-56a156d0ae2a\",\"added_by\":\"auto\",\"created_at\":\"2026-03-26 16:24:58\",\"extension\":\"png\",\"order_by\":5,\"title\":\"Figure 5\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":26041,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eQuantile regression for hospital volume and length of hospital stay (LOS). X-axis: 0.1 to 0.9 quantile of LOS. Y-axis: quantile regression coefficient of hospital volume. Black dots: regression coefficients. Red dashed line: β of the ordinary regression.\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"Fig5.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-8707208/v1/b659a73bfe52effb308bbb9b.png\"},{\"id\":105496301,\"identity\":\"048ef3f8-8fb1-47c1-9556-c086ab683383\",\"added_by\":\"auto\",\"created_at\":\"2026-03-26 16:25:53\",\"extension\":\"pdf\",\"order_by\":0,\"title\":\"\",\"display\":\"\",\"copyAsset\":false,\"role\":\"manuscript-pdf\",\"size\":1199962,\"visible\":true,\"origin\":\"\",\"legend\":\"\",\"description\":\"\",\"filename\":\"manuscript.pdf\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-8707208/v1/c2cb1430-af24-47b3-8304-3d6e85f4a33c.pdf\"},{\"id\":105496103,\"identity\":\"18fd7870-5d97-4d8a-b256-8651052e085d\",\"added_by\":\"auto\",\"created_at\":\"2026-03-26 16:25:19\",\"extension\":\"docx\",\"order_by\":1,\"title\":\"\",\"display\":\"\",\"copyAsset\":false,\"role\":\"supplement\",\"size\":37639,\"visible\":true,\"origin\":\"\",\"legend\":\"\",\"description\":\"\",\"filename\":\"Supplementarymaterial.docx\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-8707208/v1/385e9a19b5190c16c7aa8207.docx\"},{\"id\":105496095,\"identity\":\"992e6254-3b90-4cd0-a5bd-5292826899cd\",\"added_by\":\"auto\",\"created_at\":\"2026-03-26 16:25:15\",\"extension\":\"docx\",\"order_by\":2,\"title\":\"\",\"display\":\"\",\"copyAsset\":false,\"role\":\"supplement\",\"size\":20244,\"visible\":true,\"origin\":\"\",\"legend\":\"\",\"description\":\"\",\"filename\":\"TableSM1.docx\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-8707208/v1/69d093e0679a42ee324f6b4b.docx\"}],\"financialInterests\":\"No competing interests reported.\",\"formattedTitle\":\"Association between hospital volume and mortality after elective oesophageal cancer resection in Switzerland: A retrospective national registry study from 2013 to 2022\",\"fulltext\":[{\"header\":\" What does this paper add to the literature ? \",\"content\":\"\\u003cp\\u003eThis retrospective Swiss national registry study between 2013 and 2022 confirms the association between an increasing annual-hospital specific case volume of oesophageal cancer resection and improved short-term postoperative outcomes. Furthermore, the necessity of further centralisation of this highly complex procedure in Switzerland is demonstrated in order to achieve the outcome of international benchmark centres.\\u003c/p\\u003e\"},{\"header\":\"Introduction\",\"content\":\"\\u003cp\\u003eThe effect of centralisation on postoperative outcomes after oesophageal cancer resection (OCR) in Switzerland has not been highlighted yet. Oesophageal cancer is a rare malignancy in Switzerland. It accounts for only 2% of all cancers, with an annual incidence of 603 cases between 2017 and 2021.[1] The prognosis of oesophageal cancer is poor. The 437 annual oesophageal cancer-related deaths between 2017 and 2021 resulted in a low 5-year overall survival of only 30%.[2] The therapeutic management of oesophageal cancer (neoadjuvant therapy, interventional therapy, surgical technique, adjuvant therapy) was driven by innovation and changed considerably in recent years, resulting in a complex therapy algorithm.[3-7] Together with the often polymorbid patients, the very demanding surgical technique, and the challenges in postoperative management, a specialised, high-volume, interdisciplinary treatment team is required.[8, 9] The centralisation of such complex surgical procedures in specialised centres aims to build up such treatment teams, resulting in improved quality of the treatment and increased patient safety.[10] The association between a high annual hospital-specific case load of OCR (hospital volume) and improved short-term postoperative outcomes as well as long-term survival has been well documented in current scientific literature.[11, 12] International benchmark centres suggest a threshold between 20 and 40 for high-volume centres.[13, 14] A threshold value of 12 was introduced for the first time in 2013 in Switzerland.[15] The threshold and other regulations resulted in only eight hospitals with a performance mandate for OCR.[16] Previously, 69 hospitals performed OCR in Switzerland, and the in-hospital mortality of 5.9% was significantly higher compared to international benchmark centres from ESODATA (2.0%) or DUCA (2.5% to 4.4%).[13, 14, 17-19]\\u003c/p\\u003e\\n\\u003cp\\u003eThis retrospective registry study provides Swiss national data on short-term postoperative outcomes after elective OCR in Switzerland from 2013 to 2022. It aims to examine the effect of the ongoing centralisation through the association between the hospital volume and in-hospital mortality, postoperative complications, and length of hospital stay (LOS).\\u0026nbsp;\\u003c/p\\u003e\"},{\"header\":\"Materials and Methods\",\"content\":\"\\u003cp\\u003e\\u003cstrong\\u003eStudy design\\u0026nbsp;\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThis is a retrospective population-based analysis from the Swiss national inpatient registry between 2013 and 2022. The anonymised data was obtained from the Swiss Federal Statistics Office (FSO) via a data contract for the one-time delivery and use of individual data (without personal identification) in Switzerland. At the time of ordering the data in 2024, the data from 2023 was not yet available. The data contained detailed information from all Swiss hospitals\\u0026rsquo; inpatient cases between 2013 and 2022 as described in the supplementary material.\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eCase selection\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThe cases were selected according to their \\u0026ldquo;International Statistical Classification of Diseases and Related Health Problems 10\\u003csup\\u003eth\\u003c/sup\\u003e Revision\\u0026rdquo; (ICD) and \\u0026ldquo;Swiss Classification of Operations\\u0026rdquo; (CHOP) codes.[20, 21] A case was selected for OCR when at least one of the ICD codes started with C15 (malignant neoplasm of the oesophagus [oesophageal cancer] and at least one of the CHOP codes started with 42.4 (excision of the oesophagus), 42.5 (intrathoracic anastomosis on the oesophagus), or 42.6 (in front of the sternum oesophagostomy).\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003eExclusion criteria included emergency admission, incomplete case documentation, age under 20 years, and hospitalisation in non-general or non-surgical hospitals. Incomplete documentation occurs due to the strictly full calendar year (from 1\\u003csup\\u003est\\u003c/sup\\u003e January to 31\\u003csup\\u003est\\u003c/sup\\u003e December) based classification of the FSO. Data from patients hospitalised overnight on the 31\\u003csup\\u003est\\u0026nbsp;\\u003c/sup\\u003eof December are therefore incomplete.[17] The inclusion of 18- and 19-year-olds was not possible due to the data structure with five-year age groups. Other hospitals than general and surgical hospitals were excluded because of the low levels of comorbidities and the relatively low risk of dying in the hospital.[22]\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003ePrimary and secondary endpoints\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThe primary endpoint of this study was postoperative mortality, defined as in-hospital mortality.\\u003c/p\\u003e\\n\\u003cp\\u003eSecondary endpoints were postoperative complications and length of hospital stay (LOS). The analysed postoperative complications comply with ESODATA specifications and are shown in Table 3.[13]\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003eAdditional objectives were sociodemographic trends (number of operations, number of hospitals providing the operation, mean hospital volume, age, Charlson comorbidity index (CCI), sex, intensive care unit (ICU) stay, nationality, insurance, robotic access (CHOP code 00.99.50)) between 2013 and 2022.[23]\\u0026nbsp;The CCI and ICU stay were assumed as described in the supplementary material.\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eStatistical\\u0026nbsp;\\u003c/strong\\u003e\\u003cstrong\\u003eanalysis\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThe R statistical software was used for statistical analysis (www.r-project.org). A two-sided p-value of less than 0.05 was considered statistically significant. Continuous data were expressed as the mean with standard deviation (SD), interquartile range (IQR) and the range. In descriptive analysis, proportions were compared with the chi-square statistics, and continuous variables were compared with t tests and Mann‒Whitney U tests, as appropriate.\\u003c/p\\u003e\\n\\u003cp\\u003eThe associations between the hospital volume and mortality and postoperative complications were assessed by generalized additive regression models (GAM) adjusting for year of operation with random effect B-splines. The confounding variable set included sex (male vs. female), age (continuous), CCI (continuous), nationality (foreign vs. Swiss), insurance (general vs. private (semi-private and private)), hospital type (university vs. tertiary vs. other (basic hospitals and specialised surgical hospitals)). Results were additionally presented graphically with an easy-to-interpret marginal effect analysis as described in the supplementary material.[24, 25]. For the LOS, an ordinary least square regression was complemented by an in-depth analysis by quantile regression analysis to assess the associations between the hospital volume and the different lengths of the LOS, not disturbed by outliers or skewed data, as described in the supplementary material.[26]\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003eThe time trends were assessed using the nonparametric Mann-Kendall trend test from the R trend library.[27] Its value is between -1 (perfect descending trend) and +1 (perfect ascending trend) with 0 representing no trend at all.[28]\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eEthics\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThis study was approved by the Ethics Committee of Eastern Switzerland (BASEC B2025-00702), registered under ClinicalTrials.gov (NCT07022652), and is compliant with the Strengthening the Reporting of Observation in Epidemiology (STROBE) guidelines.[29] It conforms to the provisions of the Declaration of Helsinki. There were no deviations from the published protocol.\\u0026nbsp;\\u003c/p\\u003e\"},{\"header\":\"Results\",\"content\":\"\\u003cp\\u003e\\u003cstrong\\u003eCase selection\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThe dataset provided by the FSO contained data of 14\\u0026rsquo;438\\u0026rsquo;938 cases. 22\\u0026rsquo;837 cases had an oesophageal cancer diagnosis. 1\\u0026rsquo;595 cases had an OCR. Fifty-nine cases were excluded due to emergency admission, and one case was excluded due to incomplete case documentation. 1\\u0026rsquo;535 cases were included in the analysis (Fig.1).\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eCase baseline characteristics\\u0026nbsp;\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThe case baseline characteristics are shown in Table 1. The OCRs were predominantly performed at university and tertiary hospitals (39.4% and 57.4%) on men (78.4%) with a mean age of 64.7 years. Only 23.4% of the cases were treated at institutions with a hospital volume exceeding 18 cases (Fig.2).\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eMortality\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eOverall mortality was 5.3% (n=81). A higher hospital volume was associated with 27.7% lower odds for mortality for every ten additional cases (odds ratio (OR)=0.723, 95% confidence interval (CI) 0.534 to 0.981, p=0.037) (Fig.3). According to the GAM logistic regression, higher age (OR=1.028, 95%CI 1.002 to 1.055, p=0.033) and higher CCI (OR=1.218, 95%CI 1.095 to 1.355, p\\u0026lt;0.001) had higher odds for mortality. Year of operation was a significant random effect (p=0.013) (Table 2).\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003ePostoperative complications\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThe complications are shown in Table 3. The overall complication rate was 69.3% (n=1\\u0026rsquo;063). A higher hospital volume was associated with 29.5% lower odds for overall complications for every ten additional cases (OR=0.705, 95%CI 0.608 to 0.816, p\\u0026lt;0.001) (Fig.4). According to the GAM logistic regression, higher age (OR=1.022, 95%CI 1.010 to 1.034, p\\u0026lt;0.001) had higher odds while tertiary hospitals (OR=0.749, 95%CI 0.572 to 0.980, p=0.035) had lower odds for overall complications (Table 4). \\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003eThe overall anastomotic leakage rate between 2015 and 2022 was 20.7% (n=241). A higher hospital volume was not associated with lower odds for anastomotic leakage (OR=0.861, 95%CI 0.682 to 1.086, p=0.207). However, the occurrence of anastomotic leakage was strongly associated with mortality (OR 3.758, 95%CI 1.614 to 8.753, p=0.002). The associations between all other complications and hospital volume and mortality are shown in the supplementary material table SM1.\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eLength of hospital stay\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThe mean LOS was 24.8 days (SD 18.5). In ordinary regression, no association between LOS and hospital volume was observed (\\u0026beta;=0.007, 95%CI -0.093 to 0.108, p=0.889). In-depth quantile regression showed a heterogenous effect with estimates becoming increasingly negative at the higher quantiles 0.8 and 0.9 (joint p\\u0026lt;0.001) (Figure 5). However, no significant effect was evident on quantile-specific level (Table 5).\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eTrend analysis between 2013 and 2022\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eTrend analysis is shown in table 6. The annual number of hospitals providing OCR decrease from 30 in 2013 to 18 in 2022 \\u0026nbsp;(tau=-0.750, p=0.003) with its lowest number of 14 hospitals in 2021. The number of annual OCR also decreased from 183 in 2013 to 133 in 2022 (tau -0.733, p=0.003) with its lowest number of 121 in 2020. This resulted in a steady mean hospital volume between 6.1 in 2013 and 7.4 in 2022 (t=0.244, p=0.325). Further significant trends over time were evident for ICU stay (tau=-0.822, p\\u0026lt;0.001), private insurance (tau=-0.511, p=0.040), and robotic access (tau=+0.809, p=0.001) (Table 6).\\u0026nbsp;\\u003c/p\\u003e\"},{\"header\":\"Discussion\",\"content\":\"\\u003cp\\u003eThe present retrospective Swiss national registry study is the first to examine the effect of centralisation of OCR on hospital volume and short-term postoperative outcomes in Switzerland. Cases operated at institutions with higher hospital volume had lower mortality and lower postoperative complications.\\u003c/p\\u003e\\n\\u003cp\\u003eA higher hospital volume was associated with lower mortality of nearly 28% for every ten additional cases. This finding aligns with other studies investigating the association between hospital volume and postoperative outcomes in OCR. US-American, UK, German, Japanese, and Korean national registry studies have described a similar association between hospital volume and postoperative mortality.[30-35] Their study populations ranged from 4\\u0026rsquo;868 to 28\\u0026rsquo;931 cases, and the periods examined spanned from three to 15 years between 1998 and 2017. Most analyses did not compare hospital volume as a marginal effect. Hospitals were divided into three groups: low-volume (threshold between 5 to 12 cases), mid-, and high-volume (threshold between 19 to 48 cases). These findings were confirmed in a recent meta-analysis, which showed a significantly reduced relative risk of postoperative mortality by 53% in high-volume hospitals compared to low-volume hospitals (threshold 45 cases, OR=0.47, 95%CI 0.42 to 0.53).[11]\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003eOverall, the mortality of 5.3% was higher compared to the international benchmark centres from ESODATA (2.0%) or DUCA (2.5% to 4.4).[13, 14] After starting centralisation in 2013, the annual mortality rate was significantly reduced (tau=-0.511, p=0.040) between 2013 (9.3%) and 2022 (3.8%). The lowest annual mortality rate of 2.0% in 2018 can keep up with these international benchmark centres.\\u003c/p\\u003e\\n\\u003cp\\u003eA higher hospital volume was associated with lower postoperative complications of nearly 30% for every ten additional cases. Studies investigating the association between hospital volume and overall complications as a primary outcome are sparse. Most studies focus on mortality. The complete assessment of postoperative complications from large registries can be challenging. A nationwide analysis of 29\\u0026rsquo;116 patients between 2016 and 2020 from the United States focusing on minimal invasive oesophagectomy described lower odds for major complications (OR=0.83, 95%CI 0.70 to 0.96, p=0.05) in hospital with a hospital volume \\u0026gt;16.[36] DUCA showed less technical complications (OR=0.82, 95%CI 0.70 to 0.96), less anastomotic leakage (OR=0.80, 95%CI 0.66 to 0.97), and more textbook outcome (OR=1.25, 95%Cl 1.07 to 1.46) in hospitals with hospital volume \\u0026gt;39.[37] A recent meta-analysis of 177\\u0026rsquo;566 patients also showed a lower leak rate in hospitals with hospital volume \\u0026gt;36 (9.6% vs. 8.3%, p=0.040). Meta-regression confirmed an association between annual oesophagectomies per centre and anastomotic leakage (\\u0026beta;=-0.0008, SD 0.0003, p=0.0183).[38] One possible explanation for the difference to our results regarding anastomotic leakage could be the generally higher hospital volume and threshold in these studies. The overall complication rate (69.3%) and the rate of anastomotic leakage (20.7%) were just slightly higher compared to ESODATA (60.5% and 12.5%) and DUCA (56.8% to 66.4% and 18.2% to 19.3%).[13, 14] The extent to which the high-resource setting of the highly developed Swiss health care system can compensate for this remains unclear in this study.\\u003c/p\\u003e\\n\\u003cp\\u003eThe current Swiss hospital volume threshold of 12 was set in 2013 and confirmed in the first revision in 2019.[15, 16] This is significantly below the threshold for high-volume centres proposed by ESODATA (n=40 to 50), DUCA (n=20), or the German S3 guideline (n=20).[3, 13, 14] The observation that the mean hospital volume remained stable despite a reduction in the number of hospitals and number of OCR performed per year does not fully support an effect of centralisation. The reduction of surgeries between 2013 and 2022 was somewhat astonishing. Normally, as a database becomes well established, the number of surgeries increases.[39] The current national registry went in the opposite direction. There are various possible explanations. The incidence of oesophageal cancer in Switzerland decreased in the study period.[40] A more profound prevention and screening may result in an increase in detection of early-stage cases with possible endoscopic therapy. Definitive radiochemotherapy has established itself as an alternative for squamous cell carcinomas and multimorbid patients.[3] Centralisation of highly complex surgery with high perioperative risk can result in stricter case selection.[41] At least, the COVID-19 pandemic could also have contributed to a reduced number of OCR.[42] Despite the decrease in number of hospitals performing OCR, a significant proportion of the data reported in this study came from low- to mid-volume, high-resource centres, as defined by international standards. As the perioperative management of OCR is very challenging, focusing on high-volume institutions alone is not advisable. A highly competent, dedicated, and resilient surgeon must rely on an interdisciplinary team of intensive care physicians (84.6% of cases involved an ICU stay), gastroenterologists, interventional radiologists, nutrition professionals, nursing professionals, and other relevant disciplines.[43-47] Optimal outcomes rely on the synergy of a well-coordinated interdisciplinary team and a skilled surgeon with excellent intraoperative decision-making. A high hospital volume increases clinical expertise and strengthens multidisciplinary teamwork. This leads to improved patient outcomes, as demonstrated by the results of our study.\\u003c/p\\u003e\\n\\u003cp\\u003eThe data from this study, the studies mentioned above, and the international benchmark centres should be considered in the next allocation review for OCR in Switzerland, which started in July 2025. The authors suggest an upward adjustment of the threshold value.\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eStrengths and limitations\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThe strengths of this study are the high case number, the high external validity through presentation of real-world data, the national population-based coverage minimalizing selection bias, and the minimal costs per case using government-collected data.\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003eThere are some limitations next to the low- to mid-volume, high-resource setting mentioned above. Non-randomized studies only allow associations to be made, not causal statements. They carry a relevant risk of confounding by indication, time-related biases (changes in surgical, medical, and intensive care treatment) and bias from unobserved variables. The data used in this analysis were not primarily collected for research purposes and do not contain detailed clinical variables and depth. Due to the absence of the American Society of Anesthesiologists Physical Status classification, multimodal treatment strategy, surgical approach, operative details, histology, and the Clavien-Dindo classification of postoperative complications, several important patient characteristics are missing, as they are not reported in the FSO data. The transformation of clinical data into registry codes and back into clinical data makes such registry studies prone to reporting bias due to miscoding, underreporting, and incomplete documentation.[48] The effect of centralisation, whereby sicker patients are more likely to be operated on at hospitals with higher case numbers, can lead to distortions.[35, 49]\\u0026nbsp;\\u003c/p\\u003e\"},{\"header\":\"Conclusion\",\"content\":\"\\u003cp\\u003eA higher hospital volume is associated with reduced mortality and postoperative complications. The ongoing centralisation of OCR in Switzerland must be further advanced in order to enhance clinical outcomes, ensure patient safety, and be able to compare nationally with international benchmark centres.\\u0026nbsp;\\u003c/p\\u003e\"},{\"header\":\"Declarations\",\"content\":\"\\u003cp\\u003e\\u003cstrong\\u003eAuthors\\u0026rsquo; contribution statement\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eYanic Ammann Conceptualisation, data curation, investigation, methodology, visualisation, writing - original draft\\u003c/p\\u003e\\n\\u003cp\\u003eRene Warschkow Conceptualisation, data curation, formal analysis, software, validation, visualisation, writing \\u0026ndash; review \\u0026amp; editing\\u003c/p\\u003e\\n\\u003cp\\u003eMarie Klein Writing \\u0026ndash; review \\u0026amp; editing\\u003c/p\\u003e\\n\\u003cp\\u003eKristjan Ukegjini Writing \\u0026ndash; review \\u0026amp; editing\\u003c/p\\u003e\\n\\u003cp\\u003eIgnazio Tarantino Writing \\u0026ndash; review \\u0026amp; editing\\u003c/p\\u003e\\n\\u003cp\\u003eThomas Steffen Conceptualisation, resources, project administration, supervision, writing \\u0026ndash; original draft, review \\u0026amp; editing\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eFunding statement\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThomas Steffen holds a grant from the \\u0026ldquo;Stiftung Chirurgie\\u0026rdquo;, St.Gallen, Switzerland, to financially support young researchers in translation, manuscript editing, and publication costs.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eConflict of interest disclosure\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eNone of the authors has any conflicts of interest to disclose.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003ePatient consent statement\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThe data was obtained anonymously from the Swiss Federal Statistics Office (FSO) via a data contract for the one-time delivery and use of individual data (without personal identification) in Switzerland.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eEthics approval statement\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThis study was approved by the Ethics Committee of Eastern Switzerland (BASEC B2025-00702), registered under ClinicalTrials.gov (NCT07022652), and is compliant with the Strengthening the Reporting of Observation in Epidemiology (STROBE) guidelines. It conforms to the provisions of the Declaration of Helsinki.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eConsent for publication\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThis submission is to Langenbeck\\u0026apos;s Archives of Surgery. The material is original research, has not been previously published, and has not been submitted for publication elsewhere while under consideration.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eData availability / sharing statement\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThe anonymised case data supporting this study\\u0026apos;s findings can be obtained from the Swiss Federal Statistics Office (FSO).\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eAcknowledgments\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eTo medical coding expert Dr. Therese Kim for helping with the data processing.\\u003c/p\\u003e\"},{\"header\":\"References\",\"content\":\"\\u003col\\u003e\\n\\u003cli\\u003eKrebsregistrierungsstelle BfSN. Krebs, Neuerkrankungen und Sterbef\\u0026auml;lle: Anzahl, Raten, Medianalter und Risiko pro Krebsart 2024 [Available from: https://www.bfs.admin.ch/bfs/de/home/statistiken/gesundheit/gesundheitszustand/krankheiten/krebs/daten.assetdetail.33250863.html.\\u003c/li\\u003e\\n\\u003cli\\u003eKrebsliga-Schweiz. Krebs in der Schweiz: wichtige Zahlen. 2024.\\u003c/li\\u003e\\n\\u003cli\\u003eAWMF. S3-Leitlinie Diagnostik und Therapie der Plattenepithelkarzinome und Adenokarzinome des \\u0026Ouml;sophagus 2023 [Available from: https://register.awmf.org/de/leitlinien/detail/021-023OL.\\u003c/li\\u003e\\n\\u003cli\\u003eKato H, Nakajima M. Treatments for esophageal cancer: a review. Gen Thorac Cardiovasc Surg. 2013;61(6):330-5.\\u003c/li\\u003e\\n\\u003cli\\u003eLewis S, Lukovic J. Neoadjuvant Therapy in Esophageal Cancer. Thorac Surg Clin. 2022;32(4):447-56.\\u003c/li\\u003e\\n\\u003cli\\u003eWaters JK, Reznik SI. Update on Management of Squamous Cell Esophageal Cancer. Curr Oncol Rep. 2022;24(3):375-85.\\u003c/li\\u003e\\n\\u003cli\\u003eYang W, Niu Y, Sun Y. Current neoadjuvant therapy for operable locally advanced esophageal cancer. Med Oncol. 2023;40(9):252.\\u003c/li\\u003e\\n\\u003cli\\u003eChevallay M, Jung M, Chon SH, Takeda FR, Akiyama J, M\\u0026ouml;nig S. Esophageal cancer surgery: review of complications and their management. Ann N Y Acad Sci. 2020;1482(1):146-62.\\u003c/li\\u003e\\n\\u003cli\\u003eVisser MR, van Berge Henegouwen MI, van Hillegersberg R. Centralization and Quality Control in Esophageal Cancer Surgery: a Way Forward in Europe. Dis Esophagus. 2024;37(9).\\u003c/li\\u003e\\n\\u003cli\\u003eMeguid RA, Weiss ES, Chang DC, Brock MV, Yang SC. The effect of volume on esophageal cancer resections: what constitutes acceptable resection volumes for centers of excellence? J Thorac Cardiovasc Surg. 2009;137(1):23-9.\\u003c/li\\u003e\\n\\u003cli\\u003eDi J, Lu XS, Sun M, Zhao ZM, Zhang CD. Hospital volume-mortality association after esophagectomy for cancer: a systematic review and meta-analysis. Int J Surg. 2024;110(5):3021-9.\\u003c/li\\u003e\\n\\u003cli\\u003eWang Q, Mine S, Nasu M, Fukunaga T, Nojiri S, Zhang C-D. Association of hospital volume and long-term survival after esophagectomy: A systematic review and meta-analysis. Frontiers in Surgery. 2023;Volume 10 - 2023.\\u003c/li\\u003e\\n\\u003cli\\u003eKuppusamy MK, Low DE. Evaluation of International Contemporary Operative Outcomes and Management Trends Associated With Esophagectomy: A 4-Year Study of \\u0026gt;6000 Patients Using ECCG Definitions and the Online Esodata Database. Ann Surg. 2022;275(3):515-25.\\u003c/li\\u003e\\n\\u003cli\\u003eVoeten DM, Busweiler LAD, van der Werf LR, Wijnhoven BPL, Verhoeven RHA, van Sandick JW, et al. Outcomes of Esophagogastric Cancer Surgery During Eight Years of Surgical Auditing by the Dutch Upper Gastrointestinal Cancer Audit (DUCA). Ann Surg. 2021;274(5):866-73.\\u003c/li\\u003e\\n\\u003cli\\u003eHSM-Beschlussorgan. Entscheid zur Planung der hochspezialisierten Medizin (HSM) im Bereich der grossen seltenen viszeralchirurgischen Eingriffe: Oesophagusresektion 2013 [Available from: https://www.fedlex.admin.ch/eli/fga/2013/1271/de.\\u003c/li\\u003e\\n\\u003cli\\u003eHSM-Beschlussorgan. Beschluss \\u0026uuml;ber die Zuteilung der Leistungsauftr\\u0026auml;ge im Bereich der hochspezialisierten Medizin (HSM): Komplexe hochspezialisierte Viszeralchirurgie \\u0026ndash; Oesophagusresektion bei Erwachsenen 2019 [Available from: https://www.gdk-cds.ch/fileadmin/docs/public/gdk/themen/hsm/hsm_spitalliste/BB_Oesophagusresektion.pdf.\\u003c/li\\u003e\\n\\u003cli\\u003eG\\u0026uuml;ller U, Warschkow R, Ackermann CJ, Schmied B, Cerny T, Ess S. Lower hospital volume is associated with higher mortality after oesophageal, gastric, pancreatic and rectal cancer resection. Swiss Med Wkly. 2017;147:w14473.\\u003c/li\\u003e\\n\\u003cli\\u003evan der Werf LR, Busweiler LAD, van Sandick JW, van Berge Henegouwen MI, Wijnhoven BPL. Reporting National Outcomes After Esophagectomy and Gastrectomy According to the Esophageal Complications Consensus Group (ECCG). Ann Surg. 2020;271(6):1095-101.\\u003c/li\\u003e\\n\\u003cli\\u003eKaech M, Deutschmann E, Moffa G, Haak F, Bucher HC, Kettelhack C, et al. Influence of the introduction of caseload requirements on indication for visceral cancer surgery in Switzerland. Eur J Surg Oncol. 2021;47(6):1324-31.\\u003c/li\\u003e\\n\\u003cli\\u003eICD-10-GM Version 2021, Systematisches Verzeichnis, Internationale statistische Klassifikation der Krankheiten und verwandter Gesundheitsprobleme, 10. Revision, Stand: 18. September 2020: Bundesinstitut f\\u0026uuml;r Arzneimittel und Medizinprodukte (BfArM) im Auftrag des Bundesministeriums f\\u0026uuml;r Gesundheit (BMG) unter Beteiligung der Arbeitsgruppe ICD des Kuratoriums f\\u0026uuml;r Fragen der Klassifikation im Gesundheitswesen (KKG); 2020 [Available from: www.bfarm.de \\u0026ndash; Kodiersysteme \\u0026ndash; Services - Downloads \\u0026ndash; ICD-10-GM \\u0026ndash; Version 2021.\\u003c/li\\u003e\\n\\u003cli\\u003eSchweizerische Operationsklassifikation (CHOP), Systematisches Verzeichnis - Version 2025: Bundesamt f\\u0026uuml;r Statistik; 2024 [Available from: https://www.bfs.admin.ch/bfs/de/home/statistiken/kataloge-datenbanken.assetdetail.32128591.html.\\u003c/li\\u003e\\n\\u003cli\\u003evan Walraven C, Austin PC, Jennings A, Quan H, Forster AJ. A modification of the Elixhauser comorbidity measures into a point system for hospital death using administrative data. Med Care. 2009;47(6):626-33.\\u003c/li\\u003e\\n\\u003cli\\u003eCharlson ME, Pompei P, Ales KL, MacKenzie CR. A new method of classifying prognostic comorbidity in longitudinal studies: development and validation. J Chronic Dis. 1987;40(5):373-83.\\u003c/li\\u003e\\n\\u003cli\\u003eLi Z, Wood SN. Faster model matrix crossproducts for large generalized linear models with discretized covariates. Statistics and Computing. 2020;30(1):1-7.\\u003c/li\\u003e\\n\\u003cli\\u003eLong JS, Freese J. Regression Models for Categorical Dependent Variables Using Stata. 3rd ed. College Station, TX: Stata Press; 2014.\\u003c/li\\u003e\\n\\u003cli\\u003eKazemi M, Nazari S, Motamed N, Arsang-Jang S, Fallah R. Prediction of Hospitalization Length. Quantile Regression Predicts Hospitalization Length and its Related Factors better than Available Methods. Ann Ig. 2021;33(2):177-88.\\u003c/li\\u003e\\n\\u003cli\\u003eMann HB. Nonparametric Tests Against Trend. Econometrica. 1945;13(3):245-59.\\u003c/li\\u003e\\n\\u003cli\\u003eKendall MG. A new measure of rank correltation. Biometrika. 1938;30(1-2):81-93.\\u003c/li\\u003e\\n\\u003cli\\u003evon Elm E, Altman DG, Egger M, Pocock SJ, G\\u0026oslash;tzsche PC, Vandenbroucke JP. The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement: guidelines for reporting observational studies. Lancet. 2007;370(9596):1453-7.\\u003c/li\\u003e\\n\\u003cli\\u003eKim BR, Jang EJ, Jo J, Lee H, Jang DY, Ryu HG. The association between hospital case-volume and postoperative outcomes after esophageal cancer surgery: A population-based retrospective cohort study. Thorac Cancer. 2021;12(18):2487-93.\\u003c/li\\u003e\\n\\u003cli\\u003eSchlottmann F, Strassle PD, Charles AG, Patti MG. Esophageal Cancer Surgery: Spontaneous Centralization in the US Contributed to Reduce Mortality Without Causing Health Disparities. Ann Surg Oncol. 2018;25(6):1580-7.\\u003c/li\\u003e\\n\\u003cli\\u003eFuchs HF, Harnsberger CR, Broderick RC, Chang DC, Sandler BJ, Jacobsen GR, et al. Mortality after esophagectomy is heavily impacted by center volume: retrospective analysis of the Nationwide Inpatient Sample. Surg Endosc. 2017;31(6):2491-7.\\u003c/li\\u003e\\n\\u003cli\\u003eNishigori T, Miyata H, Okabe H, Toh Y, Matsubara H, Konno H, et al. Impact of hospital volume on risk-adjusted mortality following oesophagectomy in Japan. Br J Surg. 2016;103(13):1880-6.\\u003c/li\\u003e\\n\\u003cli\\u003eNimptsch U, Peschke D, Mansky T. [Minimum Caseload Requirements and In-hospital Mortality: Observational Study using Nationwide Hospital Discharge Data from 2006 to 2013]. Gesundheitswesen. 2017;79(10):823-34.\\u003c/li\\u003e\\n\\u003cli\\u003eFischer C, Lingsma H, Klazinga N, Hardwick R, Cromwell D, Steyerberg E, et al. Volume-outcome revisited: The effect of hospital and surgeon volumes on multiple outcome measures in oesophago-gastric cancer surgery. PLoS One. 2017;12(10):e0183955.\\u003c/li\\u003e\\n\\u003cli\\u003eMallick S, Chervu NL, Balian J, Charland N, Valenzuela AR, Sakowitz S, et al. Association of hospital volume and operative approach with clinical and financial outcomes of elective esophagectomy in the United States. PLoS One. 2024;19(6):e0303586.\\u003c/li\\u003e\\n\\u003cli\\u003eVoeten DM, Gisbertz SS, Ruurda JP, Wilschut JA, Ferri LE, van Hillegersberg R, et al. Overall Volume Trends in Esophageal Cancer Surgery Results From the Dutch Upper Gastrointestinal Cancer Audit. Ann Surg. 2021;274(3):449-58.\\u003c/li\\u003e\\n\\u003cli\\u003eRahouma M, Baudo M, Mynard N, Kamel M, Khan FM, Shmushkevich S, et al. Volume outcome relationship in postesophagectomy leak: a systematic review and meta-analysis. Int J Surg. 2024;110(4):2349-54.\\u003c/li\\u003e\\n\\u003cli\\u003eAlluri RK, Leland H, Heckmann N. Surgical research using national databases. Ann Transl Med. 2016;4(20):393.\\u003c/li\\u003e\\n\\u003cli\\u003eBundesamt-f\\u0026uuml;r-Statistik. Krebsmonitoring Schweiz, Speiser\\u0026ouml;hrenkrebs ICD-10 C15 2025 [Available from: https://krebs-monitoring.bfs.admin.ch/de/detail/C15.\\u003c/li\\u003e\\n\\u003cli\\u003eRamsay AI, Tomini SM, Gandhi S, Fulop NJ, Morris S. Centralisation of specialised healthcare services: a scoping review of definitions, types, and impact on outcomes. Health Soc Care Deliv Res. 2025:1-70.\\u003c/li\\u003e\\n\\u003cli\\u003eMilito P, Asti E, Resta M, Bonavina L. Minimally invasive esophagectomy for cancer in COVID hospitals and oncological hubs: are the outcomes different? Eur Surg. 2022;54(2):98-103.\\u003c/li\\u003e\\n\\u003cli\\u003eAshok A, Niyogi D, Ranganathan P, Tandon S, Bhaskar M, Karimundackal G, et al. The enhanced recovery after surgery (ERAS) protocol to promote recovery following esophageal cancer resection. Surg Today. 2020;50(4):323-34.\\u003c/li\\u003e\\n\\u003cli\\u003eHua F, Sun D, Zhao X, Song X, Yang W. Update on therapeutic strategy for esophageal anastomotic leak: A systematic literature review. Thorac Cancer. 2023;14(4):339-47.\\u003c/li\\u003e\\n\\u003cli\\u003eCaccialanza R, Da Prat V, De Luca R, Weindelmayer J, Casirati A, De Manzoni G. Nutritional support via feeding jejunostomy in esophago-gastric cancers: proposal of a common working strategy based on the available evidence. Updates Surg. 2025;77(1):153-64.\\u003c/li\\u003e\\n\\u003cli\\u003eCao Y, Han D, Zhou X, Han Y, Zhang Y, Li H. Effects of preoperative nutrition on postoperative outcomes in esophageal cancer: a systematic review and meta-analysis. Dis Esophagus. 2022;35(3).\\u003c/li\\u003e\\n\\u003cli\\u003eChen H, Ou Y, Mo L. High-quality nursing can reduce the incidence of adverse events in esophageal cancer patients after operation in the intensive care unit and improve postoperative rehabilitation. Am J Transl Res. 2021;13(10):11851-9.\\u003c/li\\u003e\\n\\u003cli\\u003eLucyk K, Tang K, Quan H. Barriers to data quality resulting from the process of coding health information to administrative data: a qualitative study. BMC Health Services Research. 2017;17(1):766.\\u003c/li\\u003e\\n\\u003cli\\u003eMunir MM, Woldesenbet S, Endo Y, Dillhoff M, Tsai S, Pawlik TM. Association of Hospital Market Competition with Outcomes of Complex Cancer Surgery. Ann Surg Oncol. 2024;31(7):4371-80.\\u003c/li\\u003e\\n\\u003c/ol\\u003e\"},{\"header\":\"Tables\",\"content\":\"\\u003cp\\u003e\\u003cstrong\\u003eTable 1\\u003c/strong\\u003e Case baseline characteristics\\u0026nbsp;\\u003c/p\\u003e\\n\\u003ctable border=\\\"0\\\" cellspacing=\\\"0\\\" cellpadding=\\\"0\\\" width=\\\"576\\\"\\u003e\\n \\u003ctbody\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eVariable\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eLabel\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eTotal n=1\\u0026rsquo;535\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eAge (years)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eMean (SD)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e64.7 (9.7)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eRange\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e22.0-87.0\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eSex\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eMale\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e1203 (78.4%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eFemale\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e332 (21.6%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eNationality\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eForeign\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e177 (11.5%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eSwiss\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e1358 (88.5%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eInsurance\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eGeneral\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e1060 (69.1%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003ePrivate\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e475 (30.9%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eCCI\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eMean (SD)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e3.8 (2.0)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eRange\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e2.0-11.0\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eUICC stage\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eI/II\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e1024 (66.7%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eIII\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e457 (29.8%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eIV\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e54 (3.5%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eType of hospital\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eUniversity\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e605 (39.4%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eTertiary\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e881 (57.4%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eOther\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e49 (3.2%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eHospital volume\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eMean (SD)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e13.7 (9.2)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eRange\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e1.0-40.0\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026gt; 12.0 (50th percentile)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e648 (42.2%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026gt; 18.0 (75th percentile)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e359 (23.4%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026gt; 26.0 (90th percentile)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e141 (9.2%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eRobotic access\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eYes\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e113 (7.4%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eICU stay\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eYes\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e1350 (87.9%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eHours on ICU\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eMean (SD)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e145.8 (260.8)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eRange\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e3.0-5026.0\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd colspan=\\\"3\\\" valign=\\\"top\\\" style=\\\"width: 576px;\\\"\\u003e\\n \\u003cp\\u003eSD: Standard deviation; CCI: Charlson comorbidity index; UICC: Union Internationale Contre le Cancer;\\u0026nbsp;\\u003cbr\\u003e\\u0026nbsp;ICU: Intensive care unit\\u0026nbsp;\\u003cbr\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003c/tbody\\u003e\\n\\u003c/table\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003e\\u0026nbsp;\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eTable 2\\u003c/strong\\u003e GAM logistic regression for mortality\\u003c/p\\u003e\\n\\u003ctable border=\\\"0\\\" cellspacing=\\\"0\\\" cellpadding=\\\"0\\\" width=\\\"425\\\"\\u003e\\n \\u003ctbody\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eVariable\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eLabel\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eOR\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003e95%CI\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003ep-value\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003eHospital volume\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003econtinuous\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003e0.723\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e0.534 to 0.981\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003e0.037\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003eAge\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003econtinuous\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003e1.028\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e1.002 to 1.055\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003e0.033\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003eSex\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003eMale\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003ereference\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e-\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e-\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003eFemale\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003e0.973\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e0.557 to 1.701\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.924\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003eCCI\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003econtinuous\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003e1.218\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e1.095 to 1.355\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003e\\u0026lt;0.001\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003eNationality\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003eForeign\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003ereference\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e-\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e-\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003eSwiss\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003e0.917\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e0.439 to 1.915\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.817\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003eInsurance\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003eGeneral\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003ereference\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e-\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e-\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003ePrivate\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003e0.865\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e0.521 to 1.436\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.575\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003eType of hospital\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003eUniversity\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003ereference\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e-\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e-\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003eTertiary\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003e0.833\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e0.487 to 1.425\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.504\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003eOther\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003e0.752\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e0.196 to 2.890\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.678\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003eYear of operation\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003eRandom effect\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003e-\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e-\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003e0.013\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd colspan=\\\"5\\\" valign=\\\"top\\\" style=\\\"width: 425px;\\\"\\u003e\\n \\u003cp\\u003eSignificant values are bold\\u003cbr\\u003e\\u0026nbsp;OR: Odds ratio; CI: Confidence interval; CCI: Charlson comorbidity index\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003c/tbody\\u003e\\n\\u003c/table\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003e\\u0026nbsp;\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eTable 3\\u0026nbsp; \\u0026nbsp; \\u0026nbsp; \\u0026nbsp;\\u003c/strong\\u003eComplications\\u003c/p\\u003e\\n\\u003ctable border=\\\"0\\\" cellspacing=\\\"0\\\" cellpadding=\\\"0\\\" width=\\\"576\\\"\\u003e\\n \\u003ctbody\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eVariable\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eLabel\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eTotal n=1\\u0026rsquo;535\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eComplications overall\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eYes\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e1063 (69.3%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eReoperation\\u0026deg;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e00.99.10\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e136 (8.9%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eMyocardial infarction*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eI21, I22\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e5 (0.3%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eCardiac arrest*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eI46\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e22 (1.4%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eArterial fibrillation*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eI48\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e353 (23.0%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eDVT and PE*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eI26.0, I26.9, I80.2\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e58 (3.8%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003ePneumonia*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eJ13-18, J85.1\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e243 (15.8%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003ePleural effusion*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eJ90, J91\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e368 (24.0%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003ePleural empyema*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eJ86.0, J86.9\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e112 (7.3%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eAspiration*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eJ69.0, J69.8, J95.4\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e124 (8.1%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eAtelectasis*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eJ98.1\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e137 (8.9%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eMediastinitis*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eJ85.3, J98.5\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e66 (4.3%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003ePneumothorax*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eJ93, J95.80, S27.0\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e166 (10.8%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eHaemothorax*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eJ94.2, S27.1, S27.2\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e9 (0.6%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003ePulmonal insufficiency, respiratory failure*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eJ95.1, J95.2, J95.3, J96\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e237 (15.4%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eARDS*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eJ80\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e37 (2.4%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eAcute kidney injury*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eN17, N19\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e116 (7.6%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eUrinary tract infection*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eN10, N30.0, N30.9, N39.0\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e52 (3.4%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eUrinary retention*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eR33\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e41 (2.7%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eAnastomotic leakage *\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003en/a 2013 and 2014\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e368 (24.0%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eNo 2015 to 2022\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e926 (79.3%)ꜝ\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eK91.83 2015 to 2022\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e241 (20.7%)ꜝ\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eAnastomotic stenosis*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eK22.2\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e69 (4.5%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eGastrointestinal ulcer*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eK25, K28\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e29 (1.9%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003ePeritonitis and intraabdominal abscess*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eK65\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e20 (1.3%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eDelayed gastric emptying*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eK31.88\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e50 (3.3%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eIleus*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eK56, K91.3\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e55 (3.6%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eBleeding*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eT81.0, S36.81\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e88 (5.7%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eShock*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eT81.1\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e5 (0.3%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eLymphatic fistula*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eI89.8, J94.0\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e58 (3.8%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eWound dehiscence*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eT81.3\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e64 (4.2%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eSSI*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eT81.4, T89.02, L08.9\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e108 (7.0%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eOther vascular complication*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eT81.7\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e1 (0.1%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eInjury to the heart*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eS26.0\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e2 (0.1%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eInjury to the lungs or pleura*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eS27.0, S21.3, S27.6\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e39 (2.5%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eTracheobronchial injury*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eS27.4, S27.5\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e10 (0.7%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eInjury to the thoracic duct*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eS27.82\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e5 (0.3%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eInjury to the diaphragm*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eS27.81\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e2 (0.1%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eInjury to other or multiple thoracal organs*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eS27.7, S27.83, S27.84, S27.88, S27.9\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e3 (0.2%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eRecurrent laryngeal nerve palsy*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eJ38, G52.2\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e61 (4.0%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eOther intraoperative injuries*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eT81.2\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e15 (1.0%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eIntraoperative retained foreign body*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eT81.5, T81.6\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e1 (0.1%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eOther complications*\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003eJ95.8, J95.9, K91.88, K91.9, T81.8, T81.9\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e200 (13.0%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd colspan=\\\"3\\\" valign=\\\"top\\\" style=\\\"width: 576px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026deg;: Swiss Classification of Operations\\u0026rdquo; (CHOP) codes\\u003cbr\\u003e\\u0026nbsp;*: International Statistical Classification of Diseases and Related Health Problems 10th Revision\\u0026rdquo; (ICD)\\u0026nbsp;\\u003cbr\\u003e\\u0026nbsp;ꜝ: total operation between 2015 and 2022 n=1\\u0026rsquo;167\\u003cbr\\u003e\\u0026nbsp;SD: Standard deviation; DVT: Deep venous thrombosis; PE: Pulmonary embolism;\\u0026nbsp;\\u003c/p\\u003e\\n \\u003cp\\u003eARDS: Acute respiratory distress syndrome; n/a: Not available; SSI: Surgical site infection\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003c/tbody\\u003e\\n\\u003c/table\\u003e\\n\\u003cp\\u003e\\u003cbr\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eTable 4 \\u0026nbsp; \\u0026nbsp; \\u0026nbsp;\\u0026nbsp;\\u003c/strong\\u003eGAM logistic regression for overall complication\\u003c/p\\u003e\\n\\u003ctable border=\\\"0\\\" cellspacing=\\\"0\\\" cellpadding=\\\"0\\\" width=\\\"425\\\"\\u003e\\n \\u003ctbody\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eVariable\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eLabel\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eOR\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003e95%CI\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003ep-value\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003eHospital volume\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003econtinuous\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003e0.705\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e0.608 to 0.816\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003e\\u0026lt;0.001\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003eAge\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003econtinuous\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003e1.022\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e1.010 to 1.034\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003e\\u0026lt;0.001\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003eSex\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003eMale\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003eRef\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e-\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e-\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003eFemale\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003e1.283\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e0.972 to 1.692\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.078\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003eCCI\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003econtinuous\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003e1.029\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e0.973 to 1.087\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.318\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003eNationality\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003eForeign\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003eRef\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e-\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e-\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003eSwiss\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003e0.728\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e0.506 to 1.047\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.087\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003eInsurance\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003eGeneral\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003eRef\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e-\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e-\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003ePrivate\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003e1.164\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e0.905 to 1.499\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.237\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003eType of hospital\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003eUniversity\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003eRef\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e-\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e-\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003eTertiary\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003e0.749\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e0.572 to 0.980\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003e0.035\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003eOther\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003e0.676\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e0.321 to 1.421\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.301\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 113px;\\\"\\u003e\\n \\u003cp\\u003eYear of operation\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"bottom\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003eRandom effect\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 66px;\\\"\\u003e\\n \\u003cp\\u003e-\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 95px;\\\"\\u003e\\n \\u003cp\\u003e-\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.107\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd colspan=\\\"5\\\" valign=\\\"top\\\" style=\\\"width: 425px;\\\"\\u003e\\n \\u003cp\\u003eSignificant values are bold\\u003cbr\\u003e\\u0026nbsp;OR: Odds ratio; CI: Confidence interval; CCI: Charlson comorbidity index\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003c/tbody\\u003e\\n\\u003c/table\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003e\\u0026nbsp;\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eTable 5\\u0026nbsp; \\u0026nbsp; \\u0026nbsp; \\u0026nbsp;\\u003c/strong\\u003eQuantile regression for length of hospital stay\\u003c/p\\u003e\\n\\u003ctable border=\\\"0\\\" cellspacing=\\\"0\\\" cellpadding=\\\"0\\\" width=\\\"359\\\"\\u003e\\n \\u003ctbody\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eQuantile\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 85px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eLOS (days)\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eCoefficient of hospital volume (95% CI)\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.1\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 85px;\\\"\\u003e\\n \\u003cp\\u003e12\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e0.057 (-0.120 to 0.094)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.2\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 85px;\\\"\\u003e\\n \\u003cp\\u003e14\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e0.000 (0.000 to 0.107)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.3\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 85px;\\\"\\u003e\\n \\u003cp\\u003e15.2\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e0.056 (-0.036 to 0.093)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.4\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 85px;\\\"\\u003e\\n \\u003cp\\u003e17\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e0.000 (0.000 to 0.082)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.5\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 85px;\\\"\\u003e\\n \\u003cp\\u003e19\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e0.000 (0.000 to 0.083)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.6\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 85px;\\\"\\u003e\\n \\u003cp\\u003e22\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e-0.028 (-0.088 to 0.160)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.7\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 85px;\\\"\\u003e\\n \\u003cp\\u003e25\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e-0.000 (-0.123 to 0.074)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.8\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 85px;\\\"\\u003e\\n \\u003cp\\u003e31\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e-0.065 (-0.177 to 0.081)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.9\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 85px;\\\"\\u003e\\n \\u003cp\\u003e43\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 217px;\\\"\\u003e\\n \\u003cp\\u003e-0.182 (-0.451 to 0.100)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" colspan=\\\"3\\\" valign=\\\"top\\\" style=\\\"width: 359px;\\\"\\u003e\\n \\u003cp\\u003eLOS: Length of hospital stay; CI: Confidence interval\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003c/tbody\\u003e\\n\\u003c/table\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003e\\u0026nbsp;\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eTable 6\\u0026nbsp; \\u0026nbsp; \\u0026nbsp; \\u0026nbsp;\\u003c/strong\\u003eTrend analysis\\u003c/p\\u003e\\n\\u003ctable border=\\\"0\\\" cellspacing=\\\"0\\\" cellpadding=\\\"0\\\" title=\\\"Table 1 \\\" width=\\\"440\\\" class=\\\"fr-table-selection-hover\\\"\\u003e\\n \\u003ctbody\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eVariable\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 90px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eSum / average\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 40px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003e2013\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 48px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003e2022\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 64px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003etau trend\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003ep value*\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003eMortality (%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 90px;\\\"\\u003e\\n \\u003cp\\u003e5.1\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 40px;\\\"\\u003e\\n \\u003cp\\u003e9.3\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 48px;\\\"\\u003e\\n \\u003cp\\u003e3.8\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 64px;\\\"\\u003e\\n \\u003cp\\u003e-0.511\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003e0.040\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003eOverall complications (%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 90px;\\\"\\u003e\\n \\u003cp\\u003e69.2\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 40px;\\\"\\u003e\\n \\u003cp\\u003e63.9\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 48px;\\\"\\u003e\\n \\u003cp\\u003e72.9\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 64px;\\\"\\u003e\\n \\u003cp\\u003e0.289\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.245\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003eNumber of operations\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 90px;\\\"\\u003e\\n \\u003cp\\u003e1\\u0026rsquo;535\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 40px;\\\"\\u003e\\n \\u003cp\\u003e183\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 48px;\\\"\\u003e\\n \\u003cp\\u003e133\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 64px;\\\"\\u003e\\n \\u003cp\\u003e-0.733\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003e0.003\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003eNumber of hospitals\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 90px;\\\"\\u003e\\n \\u003cp\\u003e19.9\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 40px;\\\"\\u003e\\n \\u003cp\\u003e30\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 48px;\\\"\\u003e\\n \\u003cp\\u003e18\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 64px;\\\"\\u003e\\n \\u003cp\\u003e-0.750\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003e0.003\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003eMean hospital volume\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 90px;\\\"\\u003e\\n \\u003cp\\u003e7.9\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 40px;\\\"\\u003e\\n \\u003cp\\u003e6.1\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 48px;\\\"\\u003e\\n \\u003cp\\u003e7.4\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 64px;\\\"\\u003e\\n \\u003cp\\u003e0.244\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.325\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003eMean age (years)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 90px;\\\"\\u003e\\n \\u003cp\\u003e64.7\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 40px;\\\"\\u003e\\n \\u003cp\\u003e64.7\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 48px;\\\"\\u003e\\n \\u003cp\\u003e66.3\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 64px;\\\"\\u003e\\n \\u003cp\\u003e0.156\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.531\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003eMean CCI\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 90px;\\\"\\u003e\\n \\u003cp\\u003e3.8\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 40px;\\\"\\u003e\\n \\u003cp\\u003e3.5\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 48px;\\\"\\u003e\\n \\u003cp\\u003e3.9\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 64px;\\\"\\u003e\\n \\u003cp\\u003e0.422\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.089\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003eWomen (%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 90px;\\\"\\u003e\\n \\u003cp\\u003e21.6\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 40px;\\\"\\u003e\\n \\u003cp\\u003e23.0\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 48px;\\\"\\u003e\\n \\u003cp\\u003e17.3\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 64px;\\\"\\u003e\\n \\u003cp\\u003e-0.156\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.531\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003eICU stay (%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 90px;\\\"\\u003e\\n \\u003cp\\u003e87.2\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 40px;\\\"\\u003e\\n \\u003cp\\u003e96.2\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 48px;\\\"\\u003e\\n \\u003cp\\u003e76.7\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 64px;\\\"\\u003e\\n \\u003cp\\u003e-0.822\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003e\\u0026lt;0.001\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003eSwiss (%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 90px;\\\"\\u003e\\n \\u003cp\\u003e88.4\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 40px;\\\"\\u003e\\n \\u003cp\\u003e85.9\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 48px;\\\"\\u003e\\n \\u003cp\\u003e90.2\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 64px;\\\"\\u003e\\n \\u003cp\\u003e0.045\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.857\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003ePrivate insurance (%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 90px;\\\"\\u003e\\n \\u003cp\\u003e30.3\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 40px;\\\"\\u003e\\n \\u003cp\\u003e31.7\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 48px;\\\"\\u003e\\n \\u003cp\\u003e26.3\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 64px;\\\"\\u003e\\n \\u003cp\\u003e-0.511\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003e0.040\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003eRobotic access (%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 90px;\\\"\\u003e\\n \\u003cp\\u003e8.07\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 40px;\\\"\\u003e\\n \\u003cp\\u003e0.0\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 48px;\\\"\\u003e\\n \\u003cp\\u003e23.3\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 64px;\\\"\\u003e\\n \\u003cp\\u003e0.809\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003e0.001\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 142px;\\\"\\u003e\\n \\u003cp\\u003eMean LOS (days)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 90px;\\\"\\u003e\\n \\u003cp\\u003e24.8\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 40px;\\\"\\u003e\\n \\u003cp\\u003e26.7\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 48px;\\\"\\u003e\\n \\u003cp\\u003e25.5\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 64px;\\\"\\u003e\\n \\u003cp\\u003e-0.200\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd nowrap=\\\"\\\" valign=\\\"top\\\" style=\\\"width: 57px;\\\"\\u003e\\n \\u003cp\\u003e0.421\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd nowrap=\\\"\\\" colspan=\\\"6\\\" valign=\\\"top\\\" style=\\\"width: 100%;\\\"\\u003e\\n \\u003cp\\u003e*Significant values are bold\\u003c/p\\u003e\\n \\u003cp\\u003eCCI: Charlson comorbidity index; ICU: Intensive care unit; LOS: Length of hospital stay\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003c/tbody\\u003e\\n\\u003c/table\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003e\\u0026nbsp;\\u003c/strong\\u003e\\u003c/p\\u003e\"}],\"fulltextSource\":\"\",\"fullText\":\"\",\"funders\":[],\"hasAdminPriorityOnWorkflow\":false,\"hasManuscriptDocX\":true,\"hasOptedInToPreprint\":true,\"hasPassedJournalQc\":\"\",\"hasAnyPriority\":false,\"hideJournal\":false,\"highlight\":\"\",\"institution\":\"\",\"isAcceptedByJournal\":false,\"isAuthorSuppliedPdf\":false,\"isDeskRejected\":\"\",\"isHiddenFromSearch\":false,\"isInQc\":false,\"isInWorkflow\":false,\"isPdf\":false,\"isPdfUpToDate\":true,\"isWithdrawnOrRetracted\":false,\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"langenbecks-archives-of-surgery\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":false,\"externalIdentity\":\"laos\",\"sideBox\":\"Learn more about [Langenbeck's Archives of Surgery](http://link.springer.com/journal/423)\",\"snPcode\":\"423\",\"submissionUrl\":\"https://submission.nature.com/new-submission/423/3\",\"title\":\"Langenbeck's Archives of Surgery\",\"twitterHandle\":\"\",\"acdcEnabled\":true,\"dfaEnabled\":true,\"editorialSystem\":\"em\",\"reportingPortfolio\":\"Springer Hybrid\",\"inReviewEnabled\":true,\"inReviewRevisionsEnabled\":false},\"keywords\":\"Oesophageal cancer, surgery, hospital volume, mortality, postoperative complications\",\"lastPublishedDoi\":\"10.21203/rs.3.rs-8707208/v1\",\"lastPublishedDoiUrl\":\"https://doi.org/10.21203/rs.3.rs-8707208/v1\",\"license\":{\"name\":\"CC BY 4.0\",\"url\":\"https://creativecommons.org/licenses/by/4.0/\"},\"manuscriptAbstract\":\"\\u003cp\\u003e\\u003cstrong\\u003ePurpose:\\u003c/strong\\u003e The association between a high annual hospital-specific case volume and improved postoperative outcomes after oesophageal cancer resection (OCR) is well described. The Swiss government started centralisation of OCR in 2013. This study investigates this centralisation in terms of the annual hospital-specific case volume of OCR (hospital volume) and its effect on short-term postoperative outcomes.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eMethods:\\u003c/strong\\u003e National inpatient registry data of all hospitals providing OCR (ICD codes C15 and at least one of the CHOP codes starting with 424, 425, or 426) between 2013 and 2022 in Switzerland were analysed. The primary endpoint was in-hospital mortality. Secondar endpoints were postoperative complications and length of hospital stay (LOS). Additional objectives were sociodemographic time trends.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eResults:\\u003c/strong\\u003e 1’535 cases were identified. The annual number of hospitals providing OCR ranged between 30 in 2013 and 14 in 2021. Hospital volume varied between one and 40 patients per year. Overall mortality was 5.3% (n=81) declining from 9.3% in 2013 to 3.8% in 2022 (t=-0.511, p=0.040). Increasing hospital volume was associated with lower risk for mortality (odds ratio (OR)=0.723, 95% confidence interval (CI) 0.53 to 0.98, p=0.037) and postoperative complications (OR=0.705, 95%CI: 0.62 to 0.83, p\\u0026lt;0.001), and shorter LOS from the 8th quantile of LOS upwards (p\\u0026lt;0.001).\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eConclusions:\\u003c/strong\\u003e A higher hospital volume is associated with reduced mortality and postoperative complications. The ongoing centralisation of OCR in Switzerland must be further advanced in order to enhance clinical outcomes, ensure patient safety, and be able to compare nationally with international benchmark centres.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eClinical trial registration\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eClinicalTrials.gov, NCT07022652, https://clinicaltrials.gov/search?id=NCT07022652\\u003c/p\\u003e\",\"manuscriptTitle\":\"Association between hospital volume and mortality after elective oesophageal cancer resection in Switzerland: A retrospective national registry study from 2013 to 2022\",\"msid\":\"\",\"msnumber\":\"\",\"nonDraftVersions\":[{\"code\":1,\"date\":\"2026-03-26 16:23:35\",\"doi\":\"10.21203/rs.3.rs-8707208/v1\",\"editorialEvents\":[{\"type\":\"communityComments\",\"content\":0},{\"type\":\"decision\",\"content\":\"Revision requested\",\"date\":\"2026-04-11T11:53:15+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"editorInvitedReview\",\"content\":\"\",\"date\":\"2026-03-31T17:51:34+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewerAgreed\",\"content\":\"198731070012841463777386891211382070094\",\"date\":\"2026-03-31T11:00:37+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewersInvited\",\"content\":\"\",\"date\":\"2026-03-24T06:01:05+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"editorAssigned\",\"content\":\"\",\"date\":\"2026-02-04T16:22:32+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"checksComplete\",\"content\":\"\",\"date\":\"2026-02-04T08:52:57+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"submitted\",\"content\":\"Langenbeck's Archives of Surgery\",\"date\":\"2026-01-27T07:14:01+00:00\",\"index\":\"\",\"fulltext\":\"\"}],\"status\":\"published\",\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"langenbecks-archives-of-surgery\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":false,\"externalIdentity\":\"laos\",\"sideBox\":\"Learn more about [Langenbeck's Archives of Surgery](http://link.springer.com/journal/423)\",\"snPcode\":\"423\",\"submissionUrl\":\"https://submission.nature.com/new-submission/423/3\",\"title\":\"Langenbeck's Archives of Surgery\",\"twitterHandle\":\"\",\"acdcEnabled\":true,\"dfaEnabled\":true,\"editorialSystem\":\"em\",\"reportingPortfolio\":\"Springer Hybrid\",\"inReviewEnabled\":true,\"inReviewRevisionsEnabled\":false}}],\"origin\":\"\",\"ownerIdentity\":\"d820df7e-d20f-4a2f-8f54-5cb7a43cb5fd\",\"owner\":[],\"postedDate\":\"March 26th, 2026\",\"published\":true,\"recentEditorialEvents\":[],\"rejectedJournal\":[],\"revision\":\"\",\"amendment\":\"\",\"status\":\"under-review\",\"subjectAreas\":[],\"tags\":[],\"updatedAt\":\"2026-04-27T18:53:35+00:00\",\"versionOfRecord\":[],\"versionCreatedAt\":\"2026-03-26 16:23:35\",\"video\":\"\",\"vorDoi\":\"\",\"vorDoiUrl\":\"\",\"workflowStages\":[]},\"version\":\"v1\",\"identity\":\"rs-8707208\",\"journalConfig\":\"researchsquare\"},\"__N_SSP\":true},\"page\":\"/article/[identity]/[[...version]]\",\"query\":{\"redirect\":\"/article/rs-8707208\",\"identity\":\"rs-8707208\",\"version\":[\"v1\"]},\"buildId\":\"XKTyCvWXoU3ODBz1xrDgd\",\"isFallback\":false,\"isExperimentalCompile\":false,\"dynamicIds\":[84888],\"gssp\":true,\"scriptLoader\":[]}","source_license":"CC-BY-4.0","license_restricted":false}