Temporal and geographical variations of urinary tract imaging: a ten-year study from Norway

Temporal and geographical variations of urinary tract imaging: a ten-year study from Norway | 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 Temporal and geographical variations of urinary tract imaging: a ten-year study from Norway Bjørn Morten Hofmann, Ingrid Brandsæter, Jan Porthun, Elin Kjelle This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9225603/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 5 You are reading this latest preprint version Abstract Objective Unexplained and unwarranted variations in healthcare provision are profound challenges in Scandinavian healthcare. Accordingly, the aim of this study is to investigate the temporal and geographical variations for specific procedures that are identified as a potential low-value services: urinary tract imaging. Methods Register study of outpatient and inpatient data for urinary tract imaging for Norway for the years 2013–2022. Data included patients’ age, examination code, examination name, modality, hospital/imaging centre, and inpatient/outpatient status. Results 747,969 urinary tract image examinations are performed in Norway over a period of 10 years, amounting 142 examinations per 10,000 persons per year with an Interquartile Range (IQR) of 20. The median number of age- and sex-adjusted examinations of CT of the urinary tract was 71 examinations per 10,000 inhabitants per year, and IQR was 10, while the median number of examinations varied between 52 and 83 while the IQR varied between 21 and 41 between the various hospital trusts. Conclusions This is the first study of the extent and variation of imaging of the urinary tract from a whole nation for as long as ten years. It documents substantial geographical and temporal variations that are difficult to explain demographically. Knowledge of such variations is crucial for the assessment of the equity of care and for tailoring the efforts to improve the quality, safety, and efficiency of imaging services. Variation urinary tract imaging safety effectiveness efficiency quality Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Introduction Equity, quality, safety, effectiveness, and sustainability are key values in Scandinavian public health services. These values are profoundly challenged by unexplained temporal and geographical variations in healthcare provision [ 1 ]. Documenting and understanding such variations are crucial for assessing and improving healthcare services [ 2 ]. One area where insights into temporal and geographical variations are of great import for healthcare improvement is low-value care [ 3 , 4 ]. A recent review documented that urinary tract imaging is a candidate for being a low-value service [ 5 ] and several studies have raised concern about their overuse and overall utility [ 6 – 10 ]. For example, studies show that abdominal CT for urolithiasis only changed patient management in 1.8% of the cases [ 5 , 9 , 11 , 12 ]. No doubt, urinary tract imaging plays a crucial role in the diagnosis, treatment, monitoring and management of various conditions affecting the kidneys, ureters, bladder, and urethra and encompasses a range of imaging modalities, including x-ray, computed tomography (CT), magnetic resonance imaging (MRI) and ultrasound [ 13 ]. While these examinations certainly can be clinically crucial, their extensive and variable use has been questioned [ 5 , 7 , 8 , 14 ]. The aim of this study therefore is to analyze the overall temporal and geographical variation in the number of urinary tract imaging in Norway from 2013 to 2022 as this is crucial in assuring the quality and equity of public health services. Accordingly, the research questions are: 1. What are the temporal variations for urinary tract imaging with respect to modalities and specific high-volume examinations? 2. What are the geographical variations for specific urinary tract imaging? 3. How do geographical variations in urinary tract imaging relate to capacity characteristics, such as number of machines and wait times? To our knowledge, this is the first study of temporal and geographical variations in urinary tract imaging for a whole nation for as long as ten years. Methods Context The public specialist healthcare system in Norway is organized in four Regional Health Authorities (RHAs): North, West, Central, and South-East. There are several hospital trusts (HT) including one or more hospitals within each RHA [ 15 ]. The Region South-East covers about 57% of the Norwegian population as it includes the capital Oslo and hosts two hospitals with national tertiary specialist health service, such as for oncology, paediatrics, trauma, and transplantations. Imaging in Norway is provided by 19 public HTs, which have one or more imaging departments and by 28 private imaging centres, which are mainly placed in the major cities. The private centres are partly commissioned by the RHAs and partly provide outpatient services for private health insurance policies and out-of-pocket payment.[ 16 ] Additionally, some hospitals run by non-profit organizations and private foundations also provide imaging services. In total 82.6% of the urinary tract examinations were performed by public services during the study period and 76.8% were outpatient examinations. Moreover, some image providers are part of hospitals run by non-profit organizations. Some private imaging providers also offer urinary tract examinations at fee-for-service or paid by private health insurers. These are few and not included. Norway has a tax-based universal health coverage system with minor co-payments for outpatient services.[ 16 ] The co-payment rate for radiology was €25 per examination in 2023 and has a ceiling of €271 for all services beyond which no co-payment is needed for the rest of the calendar year [ 17 ]. Patients arriving at emergency departments count as outpatients as long as they are not hospitalized. Moreover, Norway has been a homogenous country with small differences in morbidity, mortality and need of health services as well as socioeconomic status compared to other countries ( https://www.ssb.no/en ) [ 18 – 20 ]. Material The Norwegian Health Economics Administration (HELFO) provided outpatient data. Inpatient data was acquired directly from the HTs. Collected data include examination codes for urinary tract imaging in the Norwegian Classification of Radiological Procedures (NCRP) system, name of procedure, modality, hospital/imaging centre, patients’ age, and sex, and in-/outpatient status. Table 1 provides the codes and names of the investigated examinations. Table 1 Codes and explanations according to the Norwegian Classification of Radiological Procedures (NCRP) system. Code Description SKX0AA X-ray Overview Urinary Tract SKX0CA X-ray Urography SKX0DA X-ray micturition cystourethrography SKX0FA X-ray of the urinary tract with measurement of glomerular filtration rate KXFF00 Uroflowmetry SKX0AD CT urinary tract SKX0BD CT Kidneys and upper urinary tract SKX0BA X-ray Pyelography SKX0AK Ultrasound of the urinary tract SKA0BK Ultrasound of the kidneys SKCOAK Ultrasound of the urinary bladder TKA0AN Nuclear Medicine (NM) scintigraphy of the kidneys TKA0BN NM Renography Sample size includes all available urinary tract image examinations from 2013–2022 in Norway (747,969). All patients having imaging of the urinary tract were included. No exclusion criteria. As not all data can be presented, the examination with the highest volume and one examination with substantial geographical variation was selected for closer scrutiny, i.e., SKX0AA and SKX0AD. Moreover, these were also indicated to be of greatest interest with respect to temporal and geographical variations [ 5 , 7 , 8 , 14 ]. Data on the Norwegian population in the various geographical areas was provided by Statistics Norway provided for each year and age group. As it takes time for the HTs to provide the data, and to request, receive, and standardize the data for analyses, the newest data that can be presented is from 2022. Analyses Statistical analyses were performed with SPSS Statistics, version 28 (IBM Corp.) and Microsoft Excel 2016 was used for descriptive statistics. Age and sex adjustment were done with Direct Adjustment to the European Standard Population per 10,000 inhabitants to facilitate international comparison. While outpatient data covers the whole population, inpatient data for 11 hospitals (accounting for 32% of inpatient population) were estimated. The data on inpatient data had to be collected from each HT and data extraction was time consuming for the HTs. In order not to burden the HTs, representative HTs were selected according to size (large, medium, small), service profile (subspeciality, speciality, general), urbanicity (urban, rural), patient mix (age, gender), and access to alternative private services (easy, medium, difficult). Inpatient data were extrapolated based on population characteristics and number of outpatient examinations. HTs with similar characteristics were paired to reduce potential skewness. In total 33.4% of inpatient data were extrapolated, which amounts to 15.0% of all data. RHAs and hospital trusts (HTs) were used as geographical units in accordance to Norwegian health authorities’ organization [ 21 ]. Results In total 747,969 radiological imaging examinations of the urinary tract were performed during the ten years from 2013 to 2022, of which 82% were performed at public hospitals. This amounts to 142 examinations per 10,000 inhabitants per year on average with an IQR of 20. 44.8% of the examinations were CT of the urinary tract (SKX0AD) while 38.5% were ultrasound of the urinary tract (SKX0AK). Table 2 provides an overview over the number of examinations for the various codes for the years 2013–2022 and Fig. 1 shows the temporal variation of the various modalities for the same years. The median number of examinations per 10,000 inhabitants per year (and their IQRs) were 55 (12), 77 (12), 7 (6), and 2 (1) for ultrasound, CT, x-ray, and NM respectively. The highest number of urinary images were taken in 2014 (79,166) and least were taken in 2020 (68,800). The biggest total decrease in the use of a modality (10.8%) was for ultrasound which was reduced from 48.8% in 2015 to 37.6% in 2022. The biggest total increase (24.0%) in the use of a modality was for CT which was rose from 42.8% in 2013 to 66.8% in 2022. Table 2 Overview of the number of urinary tract examinations for the various examination codes for the years from 2013 to 2022. CT= Computed Tomography; UT= Urinary Track; US=Ultrasound; NM = Nuclear Medicine; GFR = Glomerular filtration rate. Examination NCRP-code 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 Total Percent CT urinary tract (UT) SKX0AD 23,023 34,299 32,353 35,591 36,768 37,076 38,157 32,529 33,053 32,375 335,224 44.8 US of the UT SKX0AK 30,876 31,880 32,757 31,196 29,380 28,485 28,146 24,721 25,981 24,249 287,671 38.5 CT Kidneys and upper UT SKX0BD 5,991 5,486 7,019 6,254 6,460 6,838 7,073 7,272 8,179 9,162 69,734 9.3 X-ray Overview UT SKX0AA 4149 3838 2916 2098 1417 1038 737 367 324 247 17,131 2.3 X-ray Pyelography SKX0BA 1,198 1,117 1,230 1,533 1,488 1,405 1,396 1,306 1,250 1,091 13,014 1.7 X-ray micturition cystourethrography SKX0DA 898 996 1,050 1,072 1,020 989 852 748 759 562 8,946 1.2 Ultrasound of the kidneys SKA0BK 11 4 8 26 33 441 1,165 1,162 1,371 1,251 5,472 0.7 NM Renography TKA0BN 756 684 763 646 602 569 375 283 219 165 5,062 0.7 NM scintigraphy of the kidneys TKA0AN 686 707 559 500 517 522 443 405 407 311 5,057 0.7 Uroflowmetry KXFF00 168 154 0 0 0 322 0 0 0 0 644 0.1 X-ray of UT with GFR measurement SKX0FA 2 1 1 1 0 2 7 0 0 14 0 Total All codes 67,758 79,166 78,656 78,917 77,685 77,687 78,344 68,800 71,543 69,413 747,969 100 Figure 2 shows the temporal development for the four examinations with the highest volume from 2013 to 2022 illustrating how the use of X-ray overview (SKX0AA) and ultrasound of the urinary tract (SKX0AK) declined during the 10 years while CT of the kidneys and upper urinary tract (SKX0BD) increased somewhat. CT of the urinary tract (SKX0AD) increased till 2019 but then declined. The IQRs were 10 (CT urinary tract, UT), 14 (US of the UT), 2 (CT Kidneys and upper UT), and 5 (X-ray Overview UT) respectively. There were substantial variations between the HTs in the age-and sex-adjusted average of number of urinary tract images per 10,000 persons per year. For example, there were 12.49 times number of CT of the urinary tract in Helgeland than in Vestfold in 2021, and there were 160.7 times as many overview X-ray of the urinary tract in Telemark in 2017 than in Stavanger. Figures 3 and 4 show the variation between the catchment areas for the average adjusted number of examinations for the years 2013 to 2022. The figures show a substantial geographical variation but also indicates a great temporal variation. Median number of age- and sex-adjusted examinations of CT of the urinary tract was 71 examinations per 10,000 inhabitants per year, and IQR was 10. The median varied between 52 and 83 while the IQR varied between 21 and 41 between HTs. Median number of age-and sex-adjusted X-ray overviews of the urinary tract was 3 examinations per 10,000 inhabitants per year, and IQR was 5. The median varied between 0.3 and 6.8 while the IQR varied between 0.6 and 8.6 between the HTs. Figure 5 shows the relationship between number of x-ray and CT machines and the number of examinations per 10,000 inhabitants for these modalities in 2022. Figure 5 a and b indicate that the geographical variations cannot be explained by differences in modalities (access). Figure 5 c and 5 d show the relationship between the number of CTs of the urinary tract per 10,000 inhabitants (c) and the number of CT machines (d) versus average wait time in weeks for the various hospital trusts. Differences in wait times do not seem to explain the geographical variations either. Discussion This study documents temporal and geographical variations in urinary tract imaging in Norway over a period of 10 years. A median of 142 examinations per 10,000 persons per year were performed with an IQR of 20. The age- and sex-adjusted number of images per 10,000 inhabitants varied substantially between local hospital trusts’ (HT) catchment and over time. For example, the median number of age- and sex-adjusted examinations of CT of the urinary tract was 71 examinations per 10,000 inhabitants per year, and IQR was 10. While the median varied between 52 and 83 while the IQR varied between 21 and 41 between the various HTs. There was a substantial difference in number of adjusted examinations per 10,000 inhabitants taken between the catchment areas. The very large difference in overview x-ray of the urinary tract between Telemark and Stavanger in 2017 can be due to different imaging practices in the different HTs. The difference could be due to Stavanger being a university hospital, making more advanced examinations, but as Fig. 3 shows, Telemark has more CTs as well. The difference between the catchment areas was less for CT of the urinary tract, but the smallest difference was a ratio of 3 between the highest and the lowest area. These variations may be due to supply-sensitive differences [ 2 ]. As illustrated by Figs. 5 and 6, the differences cannot be explained by access to imaging machines or differences in wait times. Moreover, the geographical differences also varied over time. This cannot be entirely explained demographically. While the share of immigrants and Norwegian-born individuals with immigrant parents has grown (from 14.1% in 2013 to 18.9% in 2022) and there are some age discrepancies between the HTs [ 22 ] these cannot explain the large temporal and geographical variations in the services documented in this study. Our results are in accordance with other studies of temporal and geographical variations in imaging internationally [ 23 – 31 ] as well as in Norway [ 11 , 28 , 32 – 36 ] and for emergency department CT for suspected urolithiasis in particular [ 6 , 8 , 9 ]. Moreover, they are consistent with OECD statistics on imaging ( https://stats.oecd.org/ ). Unwarranted variations in imaging can be due to low-value care as low-value care may be due to variations in supply-sensitive care [ 2 ] and challenges basic ethical principles, such as beneficence and justice, as some areas may provide more appropriate imaging than others [ 1 ]. However, our study shows bigger annual variations than for other examinations, e.g., for MRI examinations documented by the Health Atlas of Radiology [ 22 ]. There may be many reasons for this, such as changes or variations in examinations practices, coding practices, referral variations, examination practices, as well as relatively few examinations. The documented variations warrant further investigations (within the various HTs). A recent scoping review of low-value imaging identified four studies reporting low-value imaging of the urinary tract in terms of low impact on the treatment or at follow-up [ 5 ]. Our results are also in line with findings from the USA where there has been an increase of CT compared to other modalities without any increase in relevant diagnoses [ 9 ]. Moreover, a recent study of 189 patients in Norway demonstrated that the CTs of the kidneys, ureters and bladder had not altered the clinical outcome for most of these patients [ 37 ]. While we observed a small reduction in number of examinations during the SARS-COV-19 pandemic, the reduction was lower than for other types of imaging[ 38 ] and the imaging did not return to normal as for other examinations [ 39 ]. The general reduction in number of examinations from 2014 is due to a reduction in all modalities – most in US and least in CT. This follows a general trend in Norway where the volume of imaging increased until 2014 and decreased somewhat thereafter [ 39 ]. While this trend contrasts the development in many countries, it may be due to high imaging rates in Norway [ 40 ], an increased awareness of low-value care, and the ChoosingWisely Initiative. We also found that more than 4000 CTs were performed for persons under the age of 20. While this is only 1.2% of all examinations, it enhances concerns with respect to dose [ 10 ] especially if the value of the examination is expected to be low. Unwarranted temporal and geographical variations raise concern with respect to the quality, safety, effectiveness, and efficiency of the imaging services in Norway. Additionally, it indicates points for improvement of the services. Certainly, the average number of examinations in the country does not indicate what is “right care” for the HTs. On the contrary, the findings urge a professional debate on appropriate care. There are several limitations in this study. As explained, the data set on inpatient data was incomplete. However, the extrapolation coherent with population characteristics and outpatient examinations, pairing HTs with similar characteristics should reduce potential skewness to a minimum. Moreover, the extrapolations are only made for a minority (15.0%) of the examinations. The examinations are reported for the various HTs and not according to where the patients live. However, despite free choice of hospital in Norway, the utilization of this has been moderate and while patient migration may have some influence on the data, there are good reasons to believe that this is limited [ 41 ]. Norwegian patients tend to be very “loyal” to their local institutions. Moreover, the data sets do not contain clinical indications. To gain additional knowledge about low-value imaging of the urinary tract we need to include data on indications, diagnoses, and follow up. However, in this study the point has been to investigate the temporal and geographical variations. Correspondingly, we have not investigated other issues, such as dose, type of equipment, imaging protocols and other examination properties as well as specialist staffing, because we had no indications that such aspects played any role for the geographical and temporal variations of the number of examinations on an overall level, as investigated in this study. Moreover, more detailed analyses on wait times would be interesting, but data for more detailed or extensive analyses are not available. Due to restricted space, we have only presented results for the geographical variations for two of the many examinations. We could of course have included other examinations but chose two examinations that use ionizing radiation where one is most frequently performed, and one has very large geographical variations. Other and supplementary studies are most welcome. We have age- and sex adjusted our data (in addition to population adjustments). However, comparison show that the differences due to age- and sex adjustments are small. Moreover, other related examinations also exist, e.g., MRI of the kidney and adrenal glands. However, they were few and have therefore not been included in this study. Here it is important to notice that there are continental and national differences in imaging utilization, as MRI accounts for a large portion of clinical practice in North America. We have not done any advanced statistical analysis, as we analyzed data for an entire population. No hypotheses about the relationship between a selected group and the entire population need to be tested. However, our findings may be influenced by random variation, measurement errors, and confounding factors. One may also want to infer to future populations. While interesting and relevant, addressing our (descriptive) research questions did not require such analyses. Patients paying out of pocket are not included in this study. They have been estimated to constitute about 9% of radiological examinations in 2017 [ 22 ]. As access to private imaging providers varies across the country, this can result in underreporting of examinations in areas that have access. However, access to such services is distributed according to market and population. Moreover, persons in rural areas of Norway are used to travel far to get certain services. Additionally, clinical findings in patients paying out of pocket may direct them into the public system. Hence it is unclear what effect of out-of-pocket payment, how big it is, and how it influences the variations found in this study. Unfortunately, data from private providers and insurance companies is limited. Moreover, the findings are for specific examinations in a particular nation for a given period of time. While the results cannot be generalized to other health systems, they are of interest to other countries for comparison. Moreover, the results indicate unwarranted variations, urging more detailed studies. Further research should explore the drivers of geographical variations and search for the ‘right’ level of diagnostic imaging. In conclusion, this is the first study of the number of imaging of the urinary tract from a whole nation for as long as ten years. It documents that almost 747,969 urinary tract radiological imaging examinations are performed in Norway over a period of 10 years, amounting to 142 examinations per 10,000 inhabitants per year on average with an IQR of 20. There were substantial temporal and geographical variations in the number of examinations which are difficult to explain demographically. 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Hofmann. 2019. Geographical variations in the use of diagnostic imaging of musculoskeletal diseases in Norway. Acta Radiol 60, 9, (2018/11/13), https://doi.org/10.1177/0284185118812204 K. B. Lysdahl, and I. Borretzen. 2007. Geographical variation in radiological services: a nationwide survey. BMC Health Serv Res 7(2007/02/17), https://doi.org/10.1186/1472-6963-7-21 B. M. Hofmann, and A. M. Gransjøen. 2022. Geographical variations in the use of outpatient diagnostic imaging in Norway 2019. Acta Radiol Open 11, 2, (2022/03/08), https://doi.org/10.1177/20584601221074561 Ingelin Børretzen, Kristin Bakke Lysdahl, and Hilde Merete Olerud. 2007. Diagnostic radiology in Norway—trends in examination frequency and collective effective dose. Radiation protection dosimetry Ingvild M Rosenlund, Olav H Førde, and Arthur Revhaug. 2017. Routine deferred computed tomography for patients with suspected urolithiasis is low-value healthcare. Scandinavian Journal of Urology 51, 1, Bjørn Hofmann, Eivind Richter Andersen, and Elin Kjelle. 2021. What can we learn from the SARS-COV-2 pandemic about the value of specific radiological examinations? BMC Health Services Research 21, 1, https://doi.org/10.1186/s12913-021-07190-w Bjørn Morten Hofmann, Ingrid Øfsti Brandsæter, Eivind Richter Andersen, Jan Porthun, and Elin Kjelle. 2024. Temporal and geographical variations in diagnostic imaging in Norway. BMC Health Services Research 9, 463, https://doi.org/http://dx.doi.org10.1186/s12913-024-10869-5 OECD. 2025. Diagnostic technologies . OECD, Paris. Kristin Bakke Lysdahl. 2011. Utilization and utility of diagnostic imaging: Quantitative studies and normative considerations. Elin Kjelle, Eivind Richter Andersen, Lesley J.J. Soril, Leti van Bodefom-Vos, and Bjørn Morten Hofmann. 2021. Interventions to reduce low-value imaging – a systematic review of interventions and outcomes. BMC Health Services Research 21, 1, https://doi.org/http://dx.doi.org10.1186/s12913-021-07004-z Additional Declarations No competing interests reported. Supplementary Files SupplementaryFileVariationsinurinarytractimaging.docx Cite Share Download PDF Status: Under Review Version 1 posted Reviewers agreed at journal 06 Apr, 2026 Reviewers invited by journal 30 Mar, 2026 Editor assigned by journal 27 Mar, 2026 Submission checks completed at journal 27 Mar, 2026 First submitted to journal 25 Mar, 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-9225603","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":614404537,"identity":"8382f6a3-16f5-43d2-9684-9c0ca41ccee1","order_by":0,"name":"Bjørn Morten Hofmann","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA5klEQVRIiWNgGAWjYBACA4YDYDqBgRnMsCFFC1sCiE5j4CGshQFFy2HCWswZDx98XLmDIY+fjTvxc+GO83n20j0GzAUVuLVYNhxLNjx7hqFYso13s/TMM7eLeWTOGDDPOIPHYQfOmEk2tjEkbrjfu0Gat+12Yo9EjgEzbxteLeY/wVqO8W7+zdt2jigtZoxQLduAthwgrAXkF6DDJBJntvFus+ZtS07suZFWcJgHj1/MJQ4f/NjYZpPYz8a7+TZvm11i+4zkjY958IQYg8QBMIkqeACPBgYG/ga80qNgFIyCUTAKGBgAlShR6ZgDDTEAAAAASUVORK5CYII=","orcid":"","institution":"University of Oslo","correspondingAuthor":true,"prefix":"","firstName":"Bjørn","middleName":"Morten","lastName":"Hofmann","suffix":""},{"id":614404539,"identity":"4c206cff-fe69-48c9-ba83-80222c8d6473","order_by":1,"name":"Ingrid Brandsæter","email":"","orcid":"","institution":"Norwegian University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Ingrid","middleName":"","lastName":"Brandsæter","suffix":""},{"id":614404540,"identity":"69464a3c-f6c8-4895-a753-5b2a3d40585e","order_by":2,"name":"Jan Porthun","email":"","orcid":"","institution":"Norwegian University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Jan","middleName":"","lastName":"Porthun","suffix":""},{"id":614404542,"identity":"f60654e1-231e-4ebc-8dd9-c4144ad2d023","order_by":3,"name":"Elin Kjelle","email":"","orcid":"","institution":"University of South-Eastern Norway","correspondingAuthor":false,"prefix":"","firstName":"Elin","middleName":"","lastName":"Kjelle","suffix":""}],"badges":[],"createdAt":"2026-03-25 16:38:11","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9225603/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9225603/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":105886403,"identity":"b07edba1-374f-42eb-9379-0b74107d3ab1","added_by":"auto","created_at":"2026-04-01 07:29:24","extension":"jpeg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":167356,"visible":true,"origin":"","legend":"\u003cp\u003eTemporal variations in median number of urinary imaging examinations for the modalities CT, ultrasound (US), x-ray, and nuclear medicine (NM) examinations per 10,000 inhabitants per year.\u003c/p\u003e","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-9225603/v1/d42c18d7d30ca9e52c1fd833.jpeg"},{"id":105886471,"identity":"311d3296-7294-49b8-95c7-8dfc08d763c1","added_by":"auto","created_at":"2026-04-01 07:29:39","extension":"jpeg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":73033,"visible":true,"origin":"","legend":"\u003cp\u003eTemporal variations for the most frequent examinations of the urinary tract for the years 2013-2022 per 10,000 persons per year. UT = urinary tract.\u003c/p\u003e","description":"","filename":"floatimage2.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-9225603/v1/1de10388de26ab3fb20fa28d.jpeg"},{"id":105886408,"identity":"471dc9de-9b79-4a20-a06d-1ade7c5165cf","added_by":"auto","created_at":"2026-04-01 07:29:24","extension":"jpeg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":162746,"visible":true,"origin":"","legend":"\u003cp\u003eVariation in average number of CTs of the urinary tract per 10,000 inhabitants per year, age and sex adjusted, for 2013 - 2022 for the hospital trust catchment areas. Dots represent minimum and maximum during the years 2013-2022. UNN= University hospital of Northern Norway, AHUS = Akershus University Hospital, VVHF = Vestre Viken Hospital Trust\u003c/p\u003e","description":"","filename":"floatimage3.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-9225603/v1/17e962cbe25e03281c617a62.jpeg"},{"id":105886467,"identity":"73a52096-a870-43a7-a4bb-89fe7618c179","added_by":"auto","created_at":"2026-04-01 07:29:37","extension":"jpeg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":115319,"visible":true,"origin":"","legend":"\u003cp\u003eVariation in average number of X-ray overviews of the urinary tract per 10,000 inhabitants per year, age and sex adjusted, for 2013 - 2022 for the hospital trust catchment areas. Dots represent minimum and maximum during the years 2013-2022. UNN= University hospital of Northern Norway, AHUS = Akershus University Hospital, VVHF = Vestre Viken Hospital Trust\u003c/p\u003e","description":"","filename":"floatimage4.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-9225603/v1/a4b1c520d8fe09d6a53d1078.jpeg"},{"id":105886420,"identity":"fd05fd69-a46e-4f0f-a529-adf271826c32","added_by":"auto","created_at":"2026-04-01 07:29:24","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":202958,"visible":true,"origin":"","legend":"\u003cp\u003eScatter plot of number of x-ray machines (a) and the number of CT machines (b) versus the number of examinations per 10,000 inhabitants for the various hospital trusts for 2022 and scatter plot of number of CTs of the urinary tract per 10,000 inhabitants (c) and number of CT machines (d) versus average wait time in weeks for the various hospital trusts\u003c/p\u003e","description":"","filename":"floatimage51.png","url":"https://assets-eu.researchsquare.com/files/rs-9225603/v1/113c0d742d50d1ab51691c2a.png"},{"id":105886552,"identity":"982d04bf-18cc-4414-bcac-a06f51d846f0","added_by":"auto","created_at":"2026-04-01 07:30:04","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1268004,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9225603/v1/901ec83f-28b6-4936-9b26-22da44b06ad9.pdf"},{"id":105886485,"identity":"bfa5568f-0119-4be5-a17e-d73a30ca5da5","added_by":"auto","created_at":"2026-04-01 07:29:43","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":97703,"visible":true,"origin":"","legend":"","description":"","filename":"SupplementaryFileVariationsinurinarytractimaging.docx","url":"https://assets-eu.researchsquare.com/files/rs-9225603/v1/02826270149298f0cf8881cc.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Temporal and geographical variations of urinary tract imaging: a ten-year study from Norway","fulltext":[{"header":"Introduction","content":"\u003cp\u003eEquity, quality, safety, effectiveness, and sustainability are key values in Scandinavian public health services. These values are profoundly challenged by unexplained temporal and geographical variations in healthcare provision [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Documenting and understanding such variations are crucial for assessing and improving healthcare services [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eOne area where insights into temporal and geographical variations are of great import for healthcare improvement is low-value care [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. A recent review documented that urinary tract imaging is a candidate for being a low-value service [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e] and several studies have raised concern about their overuse and overall utility [\u003cspan additionalcitationids=\"CR7 CR8 CR9\" citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. For example, studies show that abdominal CT for urolithiasis only changed patient management in 1.8% of the cases [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eNo doubt, urinary tract imaging plays a crucial role in the diagnosis, treatment, monitoring and management of various conditions affecting the kidneys, ureters, bladder, and urethra and encompasses a range of imaging modalities, including x-ray, computed tomography (CT), magnetic resonance imaging (MRI) and ultrasound [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. While these examinations certainly can be clinically crucial, their extensive and variable use has been questioned [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe aim of this study therefore is to analyze the overall temporal and geographical variation in the number of urinary tract imaging in Norway from 2013 to 2022 as this is crucial in assuring the quality and equity of public health services. Accordingly, the research questions are:\u003c/p\u003e \u003cp\u003e1. What are the temporal variations for urinary tract imaging with respect to modalities and specific high-volume examinations?\u003c/p\u003e \u003cp\u003e2. What are the geographical variations for specific urinary tract imaging?\u003c/p\u003e \u003cp\u003e3. How do geographical variations in urinary tract imaging relate to capacity characteristics, such as number of machines and wait times?\u003c/p\u003e \u003cp\u003eTo our knowledge, this is the first study of temporal and geographical variations in urinary tract imaging for a whole nation for as long as ten years.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eContext\u003c/h2\u003e \u003cp\u003eThe public specialist healthcare system in Norway is organized in four Regional Health Authorities (RHAs): North, West, Central, and South-East. There are several hospital trusts (HT) including one or more hospitals within each RHA [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. The Region South-East covers about 57% of the Norwegian population as it includes the capital Oslo and hosts two hospitals with national tertiary specialist health service, such as for oncology, paediatrics, trauma, and transplantations.\u003c/p\u003e \u003cp\u003eImaging in Norway is provided by 19 public HTs, which have one or more imaging departments and by 28 private imaging centres, which are mainly placed in the major cities. The private centres are partly commissioned by the RHAs and partly provide outpatient services for private health insurance policies and out-of-pocket payment.[\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e] Additionally, some hospitals run by non-profit organizations and private foundations also provide imaging services. In total 82.6% of the urinary tract examinations were performed by public services during the study period and 76.8% were outpatient examinations.\u003c/p\u003e \u003cp\u003eMoreover, some image providers are part of hospitals run by non-profit organizations. Some private imaging providers also offer urinary tract examinations at fee-for-service or paid by private health insurers. These are few and not included.\u003c/p\u003e \u003cp\u003eNorway has a tax-based universal health coverage system with minor co-payments for outpatient services.[\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e] The co-payment rate for radiology was \u0026euro;25 per examination in 2023 and has a ceiling of \u0026euro;271 for all services beyond which no co-payment is needed for the rest of the calendar year [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. Patients arriving at emergency departments count as outpatients as long as they are not hospitalized.\u003c/p\u003e \u003cp\u003eMoreover, Norway has been a homogenous country with small differences in morbidity, mortality and need of health services as well as socioeconomic status compared to other countries (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.ssb.no/en\u003c/span\u003e\u003cspan address=\"https://www.ssb.no/en\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e) [\u003cspan additionalcitationids=\"CR19\" citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eMaterial\u003c/h3\u003e\n\u003cp\u003eThe Norwegian Health Economics Administration (HELFO) provided outpatient data. Inpatient data was acquired directly from the HTs. Collected data include examination codes for urinary tract imaging in the Norwegian Classification of Radiological Procedures (NCRP) system, name of procedure, modality, hospital/imaging centre, patients\u0026rsquo; age, and sex, and in-/outpatient status. Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e provides the codes and names of the investigated examinations.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eCodes and explanations according to the Norwegian Classification of Radiological Procedures (NCRP) system.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"2\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCode\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eDescription\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSKX0AA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eX-ray Overview Urinary Tract\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSKX0CA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eX-ray Urography\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSKX0DA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eX-ray micturition cystourethrography\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSKX0FA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eX-ray of the urinary tract with measurement of glomerular filtration rate\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eKXFF00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eUroflowmetry\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSKX0AD\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCT urinary tract\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSKX0BD\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCT Kidneys and upper urinary tract\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSKX0BA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eX-ray Pyelography\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSKX0AK\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eUltrasound of the urinary tract\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSKA0BK\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eUltrasound of the kidneys\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSKCOAK\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eUltrasound of the urinary bladder\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTKA0AN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNuclear Medicine (NM) scintigraphy of the kidneys\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTKA0BN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNM Renography\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eSample size includes all available urinary tract image examinations from 2013\u0026ndash;2022 in Norway (747,969). All patients having imaging of the urinary tract were included. No exclusion criteria.\u003c/p\u003e \u003cp\u003eAs not all data can be presented, the examination with the highest volume and one examination with substantial geographical variation was selected for closer scrutiny, i.e., SKX0AA and SKX0AD. Moreover, these were also indicated to be of greatest interest with respect to temporal and geographical variations [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eData on the Norwegian population in the various geographical areas was provided by Statistics Norway provided for each year and age group. As it takes time for the HTs to provide the data, and to request, receive, and standardize the data for analyses, the newest data that can be presented is from 2022.\u003c/p\u003e\n\u003ch3\u003eAnalyses\u003c/h3\u003e\n\u003cp\u003eStatistical analyses were performed with SPSS Statistics, version 28 (IBM Corp.) and Microsoft Excel 2016 was used for descriptive statistics.\u003c/p\u003e \u003cp\u003eAge and sex adjustment were done with Direct Adjustment to the European Standard Population per 10,000 inhabitants to facilitate international comparison.\u003c/p\u003e \u003cp\u003eWhile outpatient data covers the whole population, inpatient data for 11 hospitals (accounting for 32% of inpatient population) were estimated. The data on inpatient data had to be collected from each HT and data extraction was time consuming for the HTs. In order not to burden the HTs, representative HTs were selected according to size (large, medium, small), service profile (subspeciality, speciality, general), urbanicity (urban, rural), patient mix (age, gender), and access to alternative private services (easy, medium, difficult). Inpatient data were extrapolated based on population characteristics and number of outpatient examinations. HTs with similar characteristics were paired to reduce potential skewness. In total 33.4% of inpatient data were extrapolated, which amounts to 15.0% of all data.\u003c/p\u003e \u003cp\u003eRHAs and hospital trusts (HTs) were used as geographical units in accordance to Norwegian health authorities\u0026rsquo; organization [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e].\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eIn total 747,969 radiological imaging examinations of the urinary tract were performed during the ten years from 2013 to 2022, of which 82% were performed at public hospitals. This amounts to 142 examinations per 10,000 inhabitants per year on average with an IQR of 20.\u003c/p\u003e \u003cp\u003e44.8% of the examinations were CT of the urinary tract (SKX0AD) while 38.5% were ultrasound of the urinary tract (SKX0AK). Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e provides an overview over the number of examinations for the various codes for the years 2013\u0026ndash;2022 and Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e shows the temporal variation of the various modalities for the same years. The median number of examinations per 10,000 inhabitants per year (and their IQRs) were 55 (12), 77 (12), 7 (6), and 2 (1) for ultrasound, CT, x-ray, and NM respectively.\u003c/p\u003e \u003cp\u003eThe highest number of urinary images were taken in 2014 (79,166) and least were taken in 2020 (68,800). The biggest total decrease in the use of a modality (10.8%) was for ultrasound which was reduced from 48.8% in 2015 to 37.6% in 2022. The biggest total increase (24.0%) in the use of a modality was for CT which was rose from 42.8% in 2013 to 66.8% in 2022.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eOverview of the number of urinary tract examinations for the various examination codes for the years from 2013 to 2022. CT= Computed Tomography; UT= Urinary Track; US=Ultrasound; NM\u0026thinsp;=\u0026thinsp;Nuclear Medicine; GFR\u0026thinsp;=\u0026thinsp;Glomerular filtration rate.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"14\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c12\" colnum=\"12\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c13\" colnum=\"13\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c14\" colnum=\"14\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eExamination\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNCRP-code\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2013\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2014\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2015\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2016\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2017\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2018\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003e2019\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c10\"\u003e \u003cp\u003e2020\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c11\"\u003e \u003cp\u003e2021\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c12\"\u003e \u003cp\u003e2022\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c13\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c14\"\u003e \u003cp\u003ePercent\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCT urinary tract (UT)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSKX0AD\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e23,023\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e34,299\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e32,353\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e35,591\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e36,768\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e37,076\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e38,157\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e32,529\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e33,053\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e32,375\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c13\"\u003e \u003cp\u003e335,224\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003e44.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eUS of the UT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSKX0AK\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e30,876\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e31,880\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e32,757\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e31,196\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e29,380\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e28,485\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e28,146\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e24,721\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e25,981\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e24,249\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c13\"\u003e \u003cp\u003e287,671\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003e38.5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCT Kidneys and upper UT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSKX0BD\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e5,991\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e5,486\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e7,019\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e6,254\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e6,460\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e6,838\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e7,073\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e7,272\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e8,179\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e9,162\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c13\"\u003e \u003cp\u003e69,734\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003e9.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eX-ray Overview UT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSKX0AA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4149\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e3838\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e2916\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e2098\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e1417\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e1038\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e737\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e367\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e324\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e247\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c13\"\u003e \u003cp\u003e17,131\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003e2.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eX-ray Pyelography\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSKX0BA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1,198\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1,117\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1,230\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1,533\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e1,488\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e1,405\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e1,396\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e1,306\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e1,250\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e1,091\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c13\"\u003e \u003cp\u003e13,014\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003e1.7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eX-ray micturition cystourethrography\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSKX0DA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e898\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e996\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1,050\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1,072\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e1,020\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e989\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e852\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e748\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e759\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e562\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c13\"\u003e \u003cp\u003e8,946\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003e1.2\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eUltrasound of the kidneys\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSKA0BK\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e441\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e1,165\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e1,162\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e1,371\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e1,251\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c13\"\u003e \u003cp\u003e5,472\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003e0.7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNM Renography\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTKA0BN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e756\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e684\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e763\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e646\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e602\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e569\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e375\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e283\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e219\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e165\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c13\"\u003e \u003cp\u003e5,062\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003e0.7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNM scintigraphy of the kidneys\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTKA0AN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e686\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e707\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e559\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e500\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e517\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e522\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e443\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e405\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e407\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e311\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c13\"\u003e \u003cp\u003e5,057\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003e0.7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eUroflowmetry\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKXFF00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e168\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e154\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e322\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c13\"\u003e \u003cp\u003e644\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003e0.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eX-ray of UT with GFR measurement\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSKX0FA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c13\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eTotal\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAll codes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e67,758\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e79,166\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e78,656\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e78,917\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e77,685\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e\u003cb\u003e77,687\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e\u003cb\u003e78,344\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e\u003cb\u003e68,800\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e\u003cb\u003e71,543\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e\u003cb\u003e69,413\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c13\"\u003e \u003cp\u003e\u003cb\u003e747,969\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003e\u003cb\u003e100\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e shows the temporal development for the four examinations with the highest volume from 2013 to 2022 illustrating how the use of X-ray overview (SKX0AA) and ultrasound of the urinary tract (SKX0AK) declined during the 10 years while CT of the kidneys and upper urinary tract (SKX0BD) increased somewhat. CT of the urinary tract (SKX0AD) increased till 2019 but then declined. The IQRs were 10 (CT urinary tract, UT), 14 (US of the UT), 2 (CT Kidneys and upper UT), and 5 (X-ray Overview UT) respectively.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThere were substantial variations between the HTs in the age-and sex-adjusted average of number of urinary tract images per 10,000 persons per year. For example, there were 12.49 times number of CT of the urinary tract in Helgeland than in Vestfold in 2021, and there were 160.7 times as many overview X-ray of the urinary tract in Telemark in 2017 than in Stavanger.\u003c/p\u003e \u003cp\u003eFigures \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e and \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e show the variation between the catchment areas for the average adjusted number of examinations for the years 2013 to 2022. The figures show a substantial geographical variation but also indicates a great temporal variation. Median number of age- and sex-adjusted examinations of CT of the urinary tract was 71 examinations per 10,000 inhabitants per year, and IQR was 10. The median varied between 52 and 83 while the IQR varied between 21 and 41 between HTs.\u003c/p\u003e \u003cp\u003eMedian number of age-and sex-adjusted X-ray overviews of the urinary tract was 3 examinations per 10,000 inhabitants per year, and IQR was 5. The median varied between 0.3 and 6.8 while the IQR varied between 0.6 and 8.6 between the HTs.\u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e shows the relationship between number of x-ray and CT machines and the number of examinations per 10,000 inhabitants for these modalities in 2022. Figure\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003ea and b indicate that the geographical variations cannot be explained by differences in modalities (access). Figure\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003ec and \u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003ed show the relationship between the number of CTs of the urinary tract per 10,000 inhabitants (c) and the number of CT machines (d) versus average wait time in weeks for the various hospital trusts. Differences in wait times do not seem to explain the geographical variations either.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis study documents temporal and geographical variations in urinary tract imaging in Norway over a period of 10 years. A median of 142 examinations per 10,000 persons per year were performed with an IQR of 20. The age- and sex-adjusted number of images per 10,000 inhabitants varied substantially between local hospital trusts\u0026rsquo; (HT) catchment and over time. For example, the median number of age- and sex-adjusted examinations of CT of the urinary tract was 71 examinations per 10,000 inhabitants per year, and IQR was 10. While the median varied between 52 and 83 while the IQR varied between 21 and 41 between the various HTs.\u003c/p\u003e \u003cp\u003eThere was a substantial difference in number of adjusted examinations per 10,000 inhabitants taken between the catchment areas. The very large difference in overview x-ray of the urinary tract between Telemark and Stavanger in 2017 can be due to different imaging practices in the different HTs. The difference could be due to Stavanger being a university hospital, making more advanced examinations, but as Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e shows, Telemark has more CTs as well. The difference between the catchment areas was less for CT of the urinary tract, but the smallest difference was a ratio of 3 between the highest and the lowest area. These variations may be due to supply-sensitive differences [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. As illustrated by Figs.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e and 6, the differences cannot be explained by access to imaging machines or differences in wait times.\u003c/p\u003e \u003cp\u003eMoreover, the geographical differences also varied over time. This cannot be entirely explained demographically. While the share of immigrants and Norwegian-born individuals with immigrant parents has grown (from 14.1% in 2013 to 18.9% in 2022) and there are some age discrepancies between the HTs [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e] these cannot explain the large temporal and geographical variations in the services documented in this study.\u003c/p\u003e \u003cp\u003eOur results are in accordance with other studies of temporal and geographical variations in imaging internationally [\u003cspan additionalcitationids=\"CR24 CR25 CR26 CR27 CR28 CR29 CR30\" citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e] as well as in Norway [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e, \u003cspan additionalcitationids=\"CR33 CR34 CR35\" citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e] and for emergency department CT for suspected urolithiasis in particular [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Moreover, they are consistent with OECD statistics on imaging (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://stats.oecd.org/\u003c/span\u003e\u003cspan address=\"https://stats.oecd.org/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e). Unwarranted variations in imaging can be due to low-value care as low-value care may be due to variations in supply-sensitive care [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e] and challenges basic ethical principles, such as beneficence and justice, as some areas may provide more appropriate imaging than others [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. However, our study shows bigger annual variations than for other examinations, e.g., for MRI examinations documented by the Health Atlas of Radiology [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. There may be many reasons for this, such as changes or variations in examinations practices, coding practices, referral variations, examination practices, as well as relatively few examinations. The documented variations warrant further investigations (within the various HTs).\u003c/p\u003e \u003cp\u003eA recent scoping review of low-value imaging identified four studies reporting low-value imaging of the urinary tract in terms of low impact on the treatment or at follow-up [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Our results are also in line with findings from the USA where there has been an increase of CT compared to other modalities without any increase in relevant diagnoses [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Moreover, a recent study of 189 patients in Norway demonstrated that the CTs of the kidneys, ureters and bladder had not altered the clinical outcome for most of these patients [\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eWhile we observed a small reduction in number of examinations during the SARS-COV-19 pandemic, the reduction was lower than for other types of imaging[\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e] and the imaging did not return to normal as for other examinations [\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e]. The general reduction in number of examinations from 2014 is due to a reduction in all modalities \u0026ndash; most in US and least in CT. This follows a general trend in Norway where the volume of imaging increased until 2014 and decreased somewhat thereafter [\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e]. While this trend contrasts the development in many countries, it may be due to high imaging rates in Norway [\u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e40\u003c/span\u003e], an increased awareness of low-value care, and the ChoosingWisely Initiative.\u003c/p\u003e \u003cp\u003eWe also found that more than 4000 CTs were performed for persons under the age of 20. While this is only 1.2% of all examinations, it enhances concerns with respect to dose [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e] especially if the value of the examination is expected to be low.\u003c/p\u003e \u003cp\u003eUnwarranted temporal and geographical variations raise concern with respect to the quality, safety, effectiveness, and efficiency of the imaging services in Norway. Additionally, it indicates points for improvement of the services. Certainly, the average number of examinations in the country does not indicate what is \u0026ldquo;right care\u0026rdquo; for the HTs. On the contrary, the findings urge a professional debate on appropriate care.\u003c/p\u003e \u003cp\u003eThere are several limitations in this study. As explained, the data set on inpatient data was incomplete. However, the extrapolation coherent with population characteristics and outpatient examinations, pairing HTs with similar characteristics should reduce potential skewness to a minimum. Moreover, the extrapolations are only made for a minority (15.0%) of the examinations.\u003c/p\u003e \u003cp\u003eThe examinations are reported for the various HTs and not according to where the patients live. However, despite free choice of hospital in Norway, the utilization of this has been moderate and while patient migration may have some influence on the data, there are good reasons to believe that this is limited [\u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e]. Norwegian patients tend to be very \u0026ldquo;loyal\u0026rdquo; to their local institutions.\u003c/p\u003e \u003cp\u003eMoreover, the data sets do not contain clinical indications. To gain additional knowledge about low-value imaging of the urinary tract we need to include data on indications, diagnoses, and follow up. However, in this study the point has been to investigate the temporal and geographical variations. Correspondingly, we have not investigated other issues, such as dose, type of equipment, imaging protocols and other examination properties as well as specialist staffing, because we had no indications that such aspects played any role for the geographical and temporal variations of the number of examinations on an overall level, as investigated in this study. Moreover, more detailed analyses on wait times would be interesting, but data for more detailed or extensive analyses are not available.\u003c/p\u003e \u003cp\u003eDue to restricted space, we have only presented results for the geographical variations for two of the many examinations. We could of course have included other examinations but chose two examinations that use ionizing radiation where one is most frequently performed, and one has very large geographical variations. Other and supplementary studies are most welcome.\u003c/p\u003e \u003cp\u003eWe have age- and sex adjusted our data (in addition to population adjustments). However, comparison show that the differences due to age- and sex adjustments are small.\u003c/p\u003e \u003cp\u003eMoreover, other related examinations also exist, e.g., MRI of the kidney and adrenal glands. However, they were few and have therefore not been included in this study. Here it is important to notice that there are continental and national differences in imaging utilization, as MRI accounts for a large portion of clinical practice in North America.\u003c/p\u003e \u003cp\u003eWe have not done any advanced statistical analysis, as we analyzed data for an entire population. No hypotheses about the relationship between a selected group and the entire population need to be tested. However, our findings may be influenced by random variation, measurement errors, and confounding factors. One may also want to infer to future populations. While interesting and relevant, addressing our (descriptive) research questions did not require such analyses.\u003c/p\u003e \u003cp\u003ePatients paying out of pocket are not included in this study. They have been estimated to constitute about 9% of radiological examinations in 2017 [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. As access to private imaging providers varies across the country, this can result in underreporting of examinations in areas that have access. However, access to such services is distributed according to market and population. Moreover, persons in rural areas of Norway are used to travel far to get certain services. Additionally, clinical findings in patients paying out of pocket may direct them into the public system. Hence it is unclear what effect of out-of-pocket payment, how big it is, and how it influences the variations found in this study. Unfortunately, data from private providers and insurance companies is limited.\u003c/p\u003e \u003cp\u003eMoreover, the findings are for specific examinations in a particular nation for a given period of time. While the results cannot be generalized to other health systems, they are of interest to other countries for comparison. Moreover, the results indicate unwarranted variations, urging more detailed studies.\u003c/p\u003e \u003cp\u003eFurther research should explore the drivers of geographical variations and search for the \u0026lsquo;right\u0026rsquo; level of diagnostic imaging.\u003c/p\u003e \u003cp\u003eIn conclusion, this is the first study of the number of imaging of the urinary tract from a whole nation for as long as ten years. It documents that almost 747,969 urinary tract radiological imaging examinations are performed in Norway over a period of 10 years, amounting to 142 examinations per 10,000 inhabitants per year on average with an IQR of 20. There were substantial temporal and geographical variations in the number of examinations which are difficult to explain demographically.\u003c/p\u003e \u003cp\u003eKnowledge of temporal and geographical variations is crucial for the assessment of the equity of care and for subsequent efforts to improve the quality, safety, and efficiency of imaging services. A range of interventions to align imaging services are available, such as reducing supply-sensitive care [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e] and avoiding low-value imaging [\u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e].\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eA2, A3, and A4 have collected and prepared data. A1 has have analyzed the data. A1 has written the first draft of the manuscript. All authors have contributed to the revision of the manuscript approved its final version\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eBj\u0026oslash;rn Morten Hofmann. 2022. 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Interventions to reduce low-value imaging \u0026ndash; a systematic review of interventions and outcomes. \u003cem\u003eBMC Health Services Research\u003c/em\u003e 21, 1, https://doi.org/http://dx.doi.org10.1186/s12913-021-07004-z\u003c/span\u003e\u003c/li\u003e\u003c/ol\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":"[email protected]","identity":"abdominal-radiology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"aima","sideBox":"Learn more about [Abdominal Radiology](http://link.springer.com/journal/261)","snPcode":"261","submissionUrl":"https://submission.springernature.com/new-submission/261/3","title":"Abdominal Radiology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Variation, urinary tract, imaging safety, effectiveness, efficiency, quality","lastPublishedDoi":"10.21203/rs.3.rs-9225603/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9225603/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eObjective\u003c/h2\u003e \u003cp\u003eUnexplained and unwarranted variations in healthcare provision are profound challenges in Scandinavian healthcare. Accordingly, the aim of this study is to investigate the temporal and geographical variations for specific procedures that are identified as a potential low-value services: urinary tract imaging.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eRegister study of outpatient and inpatient data for urinary tract imaging for Norway for the years 2013\u0026ndash;2022. Data included patients\u0026rsquo; age, examination code, examination name, modality, hospital/imaging centre, and inpatient/outpatient status.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003e747,969 urinary tract image examinations are performed in Norway over a period of 10 years, amounting 142 examinations per 10,000 persons per year with an Interquartile Range (IQR) of 20. The median number of age- and sex-adjusted examinations of CT of the urinary tract was 71 examinations per 10,000 inhabitants per year, and IQR was 10, while the median number of examinations varied between 52 and 83 while the IQR varied between 21 and 41 between the various hospital trusts.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003eThis is the first study of the extent and variation of imaging of the urinary tract from a whole nation for as long as ten years. It documents substantial geographical and temporal variations that are difficult to explain demographically. Knowledge of such variations is crucial for the assessment of the equity of care and for tailoring the efforts to improve the quality, safety, and efficiency of imaging services.\u003c/p\u003e","manuscriptTitle":"Temporal and geographical variations of urinary tract imaging: a ten-year study from Norway","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-04-01 07:28:29","doi":"10.21203/rs.3.rs-9225603/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewerAgreed","content":"82540942458239890218728763087254134305","date":"2026-04-06T09:07:50+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-03-30T08:45:37+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-27T07:33:44+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-03-27T07:32:44+00:00","index":"","fulltext":""},{"type":"submitted","content":"Abdominal Radiology","date":"2026-03-25T16:21:55+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"abdominal-radiology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"aima","sideBox":"Learn more about [Abdominal Radiology](http://link.springer.com/journal/261)","snPcode":"261","submissionUrl":"https://submission.springernature.com/new-submission/261/3","title":"Abdominal Radiology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"bb2179d9-b82b-4395-93e3-c5d31cef8f22","owner":[],"postedDate":"April 1st, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-04-01T07:28:30+00:00","versionOfRecord":[],"versionCreatedAt":"2026-04-01 07:28:29","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9225603","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9225603","identity":"rs-9225603","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}