Socioeconomic Factors Affecting Visual Acuity in Cataract Camps

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Though temporary and resource-intensive, cataract camps provide large-scale treatment of the condition. This study sought to determine socioeconomic factors that affect short-term improvements in visual acuity observed in cataract camps across 17 countries. Methods This observational study represents 52 camps in 17 low- and middle-income countries. Mixed-effects linear regression models were used to analyze associations between changes in LogMAR score of uncorrected visual acuity (UCVA) one to four days post-operation and socioeconomic factors including per capita GDP, Human Development Index, Cataract Surgical Rate, and density of in-country ophthalmologists. Findings Among 4110 patients, after accounting for age and sex, LogMAR UCVA significantly decreased over the first four days postoperatively (p < 0·0001). This decrease was also associated with the number of ophthalmologists per million performing cataract surgery (p = 0·0227). Patients who underwent extracapsular cataract extraction (ECCE) exhibited a greater decrease in LogMAR UCVA per day post-op (p < 0·0001). Per capita GDP was not significantly associated with the change in LogMAR UCVA per day post-op. Interpretation Our analyses suggest that cataract camps in areas with fewer ophthalmologists performing cataract surgery and ECCE surgeries correlated with the most improvement in vision. Targeting such populations and training local ophthalmologists to perform ECCE surgery may yield a higher impact in low-resource settings with a high burden of cataract-induced blindness. Cataracts world blindness socioeconomic disparity global health cataract camp blindness prevention Figures Figure 1 Introduction Cataracts are the leading cause of avoidable blindness, accounting for nearly half of world blindness in 2020 [ 1 ]. There is a significant disparity in the prevalence of cataracts and access to treatment in socioeconomically vulnerable populations. This treatment gap is widening due to globally aging demographics [ 1 – 5 ]. Although the benefits of surgery have been well documented, there is scarce evidence on which strategies work best to address this inequity in low-resource settings [ 6 ]. A mobile eye surgical unit, or a “cataract camp,” has been suggested as a safe, viable, and cost-efficient model to address the backlog of cataract-induced blindness [ 7 – 10 ]. By bringing experienced foreign or local ophthalmologists to areas inaccessible to care, cataract camps could improve vision, quality of life, and potentially the local economy as well [ 9 – 11 ]. Although there have been numerous studies on the efficacy of cataract camps in one or a few countries, a multinational study that reports a larger and more diverse body of cataract camp data has been absent, making it challenging to apply findings from one country to another. Therefore, this study presents visual acuity data collected across 17 low- and middle-income countries (LMICs) by Vision Care, an international blindness relief organization that has operated over 300 short-term cataract camps since 2002. The goal of the study is threefold. First, to assess the correlation of the visual acuity and known country-level socioeconomic factors including Gross Domestic Product (GDP), Human Development Index (HDI), and Cataract Surgical Rate (CSR). Second, to assess its correlation to existing ophthalmologist workforce in each country. Third, to assess the differences in cataract surgery outcomes based on the type of surgical technique utilized. Methods This study was conducted in accordance with the tenets of the Declaration of Helsinki and was exempt from the institutional review board at Oregon Health and Science University. Study Population This observational study utilized de-identified data from Vision Care. The patients underwent cataract surgery between 2013 and 2023. The information used for analysis included the date of surgery, age, sex, type of surgical technique, preoperative visual acuity, postoperative visual acuity, and the country in which the surgery was performed. Uncorrected visual acuities (UCVA) were measured on ordinal scales such as no light perception (LP-), light perception (LP+), count fingers (CF), or hand motion (HM) at varying distances, or on Snellen scales on Snellen chart, a number chart, or a tumbling E chart. Only cataract extraction with intraocular lens (IOL) implant cases were included in the analysis. Cases with additional surgical treatments were excluded. For example, pterygium surgery, IOL exchange, IOL repositioning that may or may not have been paired with cataract extraction were excluded. Cataract Camp Settings The cataract camps were carried out in areas where Vision Care was invited by the local government. This study reflects cataract camps in the following countries: Bangladesh, Cambodia, China, Kyrgyzstan, Mauritania, Mongolia, Morocco, Mozambique, Nigeria, Pakistan, Peru, Sri Lanka, Tanzania, Uganda, Uzbekistan, Vanuatu, and Vietnam. In each camp, locally available equipment was used, and unavailable equipment was brought in via air transportation. Camp participants were trained volunteers or Vision Care staff, with each camp having a unique set of members with a few returning volunteers. Surgical type was determined by the operating surgeon following a slit lamp exam. Individual IOL calculation and intraocular pressure (IOP) measurement were performed preoperatively. In general, extracapsular cataract extraction (ECCE) in a manual small incision cataract surgery (MSICS) fashion was preferred for dense and mature cataracts. Phacoemulsification was preferred if the cataract was deemed soft. The operating ophthalmologists were trained in the United States or South Korea, with a few local ophthalmologists operating under direct supervision of experienced surgeons. Operated patients were followed up the morning after the surgery and again on the last day of the camp for a second evaluation. During the one-week camp period, surgeries were performed Monday through Thursday, and Friday was dedicated to emergency cases and final follow-ups. Socioeconomic Factors This study used country GDP per capita in 2021 constant international dollars with the purchasing power parity (PPP) calculations to adjust for economic inflation and account for differences in cost of living [ 12 ]. The HDI summarizes the following four dimensions of socioeconomic factors: life expectancy, mean years of schooling, expected years of schooling, and gross national income (GNI) per capita [ 13 ]. The CSR reports the number of cataract surgeries performed per million populations in a year [ 14 ]. The number of ophthalmologists and the number of ophthalmologists performing cataract surgery per capita by country were obtained from a study published in 2020 by Resnikoff and colleagues [ 15 ]. Statistical Analysis The visual acuity data were converted into a LogMAR scale for ease of comparison. Snellen values were converted using the formula below: LogMAR UCVA = − 1∗𝑙𝑜𝑔10(Fraction as a Decimal) Visual acuities measured by various distances of hand motion (HM) and count finger (CF) were converted to LogMAR UCVA using methods previously described,using the mean distal interphalangeal (DIP) joint width, including inter-digit spaces, of 86.07mm [ 16 – 18 ]. To assess for changes in LogMAR UCVA between pre-operation and one, two, three, or four days post-operation, four paired Wilcoxon tests were conducted. Bonferroni corrections were applied to p-values. Multivariable mixed-effects linear regression models were used to assess for the change in LogMAR UCVA over the first four days after surgery, accounting for age and sex, both overall as well as within each country. Similar models were used to assess for interactions between the change in LogMAR UCVA over the first four days after surgery, accounting for patient age and sex, and the following variables: surgery type, GDP PPP per capita, HDI, CSR, number of ophthalmologists per capita, and number of ophthalmologists per capita performing cataract surgery. After accounting for GDP PPP, the interactions between number of ophthalmologists, number of ophthalmologists performing cataract surgery, and HDI were also assessed. Results Data was collected on 4120 eyes from 4110 patients from 52 cataract camps held between February 2013 and November 2023. Ages ranged from 3 to 109 years, with a mean of 66·9 years (Table 1). 55·2% of patients were female. 78·9% of patients underwent phacoemulsification, 20·6% underwent ECCE, and 0·4% underwent intracapsular cataract extraction (ICCE). Cataract operations were performed in 17 countries: Bangladesh, Cambodia, China, Kyrgyzstan, Mauritania, Mongolia, Morocco, Mozambique, Nigeria, Pakistan, Peru, Sri Lanka, Tanzania, Uganda, Uzbekistan, Vanuatu, and Vietnam. Most data were reported from China (15·9%), Morocco (15·6%), Tanzania (8·1%), Kyrgyzstan (8%), or Uzbekistan (7·7%). Only 1·2% of data were from Sri Lanka. Table 1: Patient demographics. N = 4,110 1 Age (years) 66·9 (3·0, 109·0) (Missing) 5 Sex Female 2,269 (55%) Male 1,840 (45%) (Missing) 1 Operation Type ECCE 847 (21%) ICCE 15 (0·4%) Phacoemulsification 3,243 (79%) (Missing) 5 Country Bangladesh 186 (4·5%) Cambodia 97 (2·4%) China 654 (16%) Kyrgyzstan 330 (8·0%) Mauritania 180 (4·4%) Mongolia 68 (1·7%) Morocco 643 (16%) Mozambique 219 (5·3%) Nigeria 101 (2·5%) Pakistan 300 (7·3%) Peru 56 (1·4%) Sri Lanka 49 (1·2%) Tanzania 332 (8·1%) Uganda 232 (5·6%) Uzbekistan 317 (7·7%) Vanuatu 53 (1·3%) Vietnam 293 (7·1%) 1 Mean (Min, Max); n (%) Pre-Operative Visual Acuity Preoperative visual acuities were available for 3976 surgeries from 3955 eyes from 3945 patients. Among the 3976 surgeries with documented preoperative visual acuities, 3060 (77%) presented with a visual acuity of 20/200 or worse. As compared to ECCE, phacoemulsification eyes had significantly lower preoperative logMAR UCVA by an average of 0·834 units (p < 0·0001). There was a significant association between preoperative logMAR UCVA and GDP PPP per capita (p < 0·0001), with preoperative logMAR UCVA decreasing by an average of 0·028 units for every 1,000-unit increase in GDP PPP per capita (95% CI: 0·022 to 0·033). There was a significant association between preoperative logMAR UCVA and HDI (p < 0·0001), with preoperative logMAR UCVA decreasing by an average of 0·9 units for every 1-unit increase in HDI (95% CI: 0·62 to 1·18). There was a significant association between preoperative logMAR UCVA and CSR per million (p = 0·0002), with preoperative logMAR UCVA decreasing by an average of 0·073 units for every 1,000-unit increase in CSR per million (95% CI: 0·035 to 0·11). There was a significant association between preoperative logMAR UCVA and the number of ophthalmologists per million citizens performing cataract surgery (p < 0·0001), with preoperative logMAR UCVA decreasing by an average of 0·053 units for every 1 additional ophthalmologist per million citizens performing cataract surgery (95% CI: 0·045 to 0·061). There was not a significant association between preoperative logMAR UCVA and the number of ophthalmologists per million citizens (p = 0·2741). Changes in Visual Acuity The mean LogMAR UCVA for all patients changed from 1·66 preoperatively to 0·964 one day postoperatively, 0·864 at two days, 0·805 at three days, and 0·79 at four days. There was a significant improvement from preoperative visual acuity at one day (p < 0·0001), two days (p < 0·0001), three days (p < 0·0001), and four days (p < 0·0001) postoperatively. (Table 2). Table 2: Summary of LogMAR UCVA preoperation and one, two, three, or four days postoperation. Preoperation N = 3,955 1 One Day Postoperation N = 3,591 1 Two Days Postoperation N = 798 1 Three Days Postoperation N = 741 1 Four Days Postoperation N = 483 1 LogMAR UCVA 1·657 (0·000, 3·079) 0·962 (-0·140, 3·079) 0·865 (-0·176, 3·079) 0·807 (-0·523, 3·000) 0·789 (-0·806, 3·000) Median decrease in LogMAR UCVA ·· 0·650 0·875 0·835 0·778 P-Value ·· < 0·0001 < 0·0001 < 0·0001 < 0·0001 1 Mean (Min, Max) There was a significant association between calculated LogMAR UCVA and days post-operation (p < 0·0001; conditional R 2 = 0.42), with LogMAR UCVA decreasing by an average of 0·286 units per day post-operation (95% CI: 0·274 to 0·298; Figure A1). This significant decrease in LogMAR UCVA per day was consistent across all 17 countries (p < 0·001). After accounting for age and sex, there was a significant interaction between the change in logMAR UCVA per day after surgery and preoperative logMAR UCVA (p < 0·0001), with logMAR UCVA decreasing by an additional 0·054 units for every 1 additional unit in preoperative logMAR UCVA (95% CI: 0·041 to 0·067 additional units). As compared to patients who underwent phacoemulsification, patients who underwent ECCE exhibited a greater decrease in LogMAR UCVA per day (p < 0·0001), decreasing by 0·175 additional units per day (95% CI: 0·146 to 0·205; Figure 1). The decrease in LogMAR UCVA per day was significantly greater in countries with fewer ophthalmologists per million performing cataract surgery (p < 0·0001). Between the first quartile of number of ophthalmologists performing cataract surgery per million citizens of 1·7 and the third quartile of 9·9, the average decrease in LogMAR UCVA per day post-operation decreased from 0·352 to 0·274 units per day. This association remained after accounting for GDP PPP per capita (p = 0·0024). The decrease in LogMAR UCVA per day was not significantly associated with the ophthalmologists per million (p = 0·7462), HDI (p = 0·716), CSR per million (p = 0·7532), or GDP PPP per capita (p = 0·8059). Discussion In this study, we reported the outcomes of 52 cataract camps from 17 LMICs. Our global data demonstrates a highly significant and consistent improvement in visual acuity from day one through four (p < 0·0001) after the surgery. This trend was universal across all countries in this study, suggesting a strong argument for the model’s replicability and generalizability. We found that the rate of improvement in vision was significantly higher in patients who presented with worse preoperative vision. This tells us that cataract surgery brings the most benefits to the population with the highest burden of unoperated, longstanding cataracts, which contribute to avoidable blindness in many LMICs. The rate of improvement was also significantly higher in those who underwent ECCE surgery than phacoemulsification. The observed faster initial recovery with the ECCE/MSICS method supports its use as a pragmatic approach in low-resource settings for treating severe cataracts, consistent with previous studies [ 9 , 19 ]. Contrary to expectations, broader national-level indicators, including total ophthalmologists per capita, HDI, CSR, and GDP PPP, were not significantly associated with the daily rate of visual recovery. (p > 0·7 for all) This suggests that these short-term postoperative outcomes are more strongly influenced by individual-level factors, such as baseline UCVA and surgical type, rather than by macroeconomic context. This finding appears to contrast with prior reports on global disparities in visual impairment, which emphasized the importance of economic indicators in estimating healthcare access and visual outcomes [ 2 – 4 ]. One possible explanation lies in the site selection process of Vision Care. The camp sites are typically chosen based on requests from local governments or partner organizations, selecting areas with higher demand for cataract surgery. As a result, the national socioeconomic indices used in this analysis may not accurately reflect the specific regions where Vision Care operates, particularly considering the substantial disparities in wealth and healthcare access within each country. Notably, however, the daily rate of visual improvement was significantly higher in countries with the lowest density of local cataract surgeons (p < 0·0001), a relationship that remained significant even after controlling for national GDP PPP (p = 0·0024). This suggests that cataract camps are most impactful where local eye care infrastructure is the weakest, further supporting the role of cataract camp as an effective and essential mechanism for closing the growing treatment gap in socioeconomically vulnerable regions. The persistence of this association after controlling for GDP PPP emphasizes that the scarcity of trained surgeons, rather than general economic development, is the primary constraint that cataract camps are designed to overcome. This result is particularly relevant in the context of globally aging population and the subsequently increasing demand for eye health services including cataract surgery. Given these results, our study strongly advocates the importance of training and incentivizing local ophthalmologists in LMICs to perform cataract surgery, with or without the aid of cataract camps. Organizations like Vision Care have been actively involved in equipping local eye care providers and ophthalmologists to expand vision screening and perform cataract surgeries. These educational initiatives can not only improve the efficiency of cataract camps but also strengthen local ophthalmologists by offering direct hands-on training from experienced surgeons. Given the marked shortage of ophthalmologists in LMICs, training competent eye care professionals who take on the challenge locally will be critical in achieving a sustainable eye care model [ 4 , 20 ]. This study has several limitations inherent to the analysis of observational data from a mass campaign format. First, our visual acuity data is limited to uncorrected visual acuity (UCVA) and does not include best-corrected visual acuity (BCVA). While UCVA is a practical and relevant outcome for evaluating the functional success of cataract camps, it may not capture the full rehabilitative potential. Second, the follow-up period is limited to the duration of the camp, preventing an assessment of long-term surgical outcomes, stability of vision, or post-operative complication rates. Yet, previous studies have suggested that such short-term visual acuity is still a valuable quality control measure in areas with poor follow-up rates [ 21 , 22 ]. Finally, the use of macro-level socioeconomic indicators may obscure heterogeneity within each country. To our knowledge, this study is the largest studies of multinational cataract camps, involving data from 17 LMICs and over four thousand patients. We conclude that cataract camps may yield the greatest impact in populations with the most severe cataracts and in countries facing the greatest shortage of local cataract surgeons. To tackle the growing global challenge of vision impairment, clinicians and policymakers must continue to support high-volume, targeted interventions like cataract camps while simultaneously focusing on building sustainable local surgical capacity. Declarations Funding source This study involves the NEI P30 EY010572 core grant and an unrestricted grant from Research to Prevent Blindness to the Casey Eye Institute of Oregon Health and Science University. The authors have not been paid to write this article. The authors were not precluded from accessing data in the study and they accept responsibility to submit for publication. All authors had access to the data and had distinctive role in writing the manuscript. - Eunyoo Kim: conceptualization, data curation, investigation, methodology, resources, writing — original draft, writing — review & editing. - Elizabeth White: Formal analysis, writing — original draft, writing — review & editing. - Dongseok Choi: Formal analysis, writing — review & editing. - Dong-wouk Park: conceptualization, methodology, project administration, resources, writing — original draft, writing — review & editing. References GBD 2019 Blindness and Vision Impairment Collaborators, & Vision Loss Expert Group of the Global Burden of Disease Study. Causes of blindness and vision impairment in 2020 and trends over 30 years, and prevalence of avoidable blindness in relation to VISION 2020: the Right to Sight: an analysis for the Global Burden of Disease Study. The Lancet. Global health 2021; 9 (2): e144–e160. doi:10.1016/S2214-109X(20)30489-7 Wang W, Yan W, Fotis K, et al. 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A prospective randomized clinical trial of phacoemulsification vs manual sutureless small-incision extracapsular cataract surgery in Nepal. Am J Ophthalmol 2007; 143 (1): 32–38. doi:10.1016/j.ajo.2006.07.023 Resnikoff S, Felch W, Gauthier TM, Spivey B. The number of ophthalmologists in practice and training worldwide: a growing gap despite more than 200,000 practitioners. Br J Ophthalmol 2012; 96 (6): 783–787. doi:10.1136/bjophthalmol-2011-301378 Aliyu H, Mustak H, Cook C. Using the Postoperative Visual Acuity to Monitor the Quality of Cataract Surgery: Does the Day One Visual Acuity following Cataract Surgery Correlate with the Final Visual Acuity?. Middle East Afr J Ophthalmol 2017; 24 (2): 91–93. doi:10.4103/meajo.MEAJO_279_16 Kurian DE, Amritanand A, Mathew M, Keziah M, Rebekah G. Correlation between visual acuity at discharge and on final follow-up in patients undergoing manual small incision cataract surgery. Indian J Ophthalmol 2021; 69 (3): 586–589. doi:10.4103/ijo.IJO_986_20 Additional Declarations No competing interests reported. Supplementary Files Appendix.docx Cite Share Download PDF Status: Published Journal Publication published 06 Apr, 2026 Read the published version in International Ophthalmology → Version 1 posted Editorial decision: Revision requested 04 Mar, 2026 Reviews received at journal 03 Mar, 2026 Reviews received at journal 15 Jan, 2026 Reviewers agreed at journal 14 Jan, 2026 Reviewers agreed at journal 14 Jan, 2026 Reviewers invited by journal 12 Jan, 2026 Editor assigned by journal 24 Dec, 2025 Submission checks completed at journal 24 Dec, 2025 First submitted to journal 23 Dec, 2025 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. 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11:58:08","extension":"html","order_by":10,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":114608,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-8437303/v1/9d96fc09191d8082f2b8a945.html"},{"id":100400619,"identity":"69b4698c-91a0-4f9e-8c1a-d68e5ac7e7d8","added_by":"auto","created_at":"2026-01-16 11:58:20","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":107398,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eChange in LogMAR UCVA per day postoperation by type of surgical technique.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-8437303/v1/ce5dc260e22de533a1cc38ef.png"},{"id":106809214,"identity":"36f5000f-0a04-4d8d-98db-0581fec50ec2","added_by":"auto","created_at":"2026-04-13 16:08:31","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":740060,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8437303/v1/977c9667-138d-439c-89da-919abc5b3ed7.pdf"},{"id":100401413,"identity":"af17150d-608e-41f2-9628-25a821b15e46","added_by":"auto","created_at":"2026-01-16 11:58:53","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":467551,"visible":true,"origin":"","legend":"","description":"","filename":"Appendix.docx","url":"https://assets-eu.researchsquare.com/files/rs-8437303/v1/aee0858551cbb5ed37f82cb8.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Socioeconomic Factors Affecting Visual Acuity in Cataract Camps","fulltext":[{"header":"Introduction","content":"\u003cp\u003eCataracts are the leading cause of avoidable blindness, accounting for nearly half of world blindness in 2020 [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. There is a significant disparity in the prevalence of cataracts and access to treatment in socioeconomically vulnerable populations. This treatment gap is widening due to globally aging demographics [\u003cspan additionalcitationids=\"CR2 CR3 CR4\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Although the benefits of surgery have been well documented, there is scarce evidence on which strategies work best to address this inequity in low-resource settings [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eA mobile eye surgical unit, or a \u0026ldquo;cataract camp,\u0026rdquo; has been suggested as a safe, viable, and cost-efficient model to address the backlog of cataract-induced blindness [\u003cspan additionalcitationids=\"CR8 CR9\" citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. By bringing experienced foreign or local ophthalmologists to areas inaccessible to care, cataract camps could improve vision, quality of life, and potentially the local economy as well [\u003cspan additionalcitationids=\"CR10\" citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eAlthough there have been numerous studies on the efficacy of cataract camps in one or a few countries, a multinational study that reports a larger and more diverse body of cataract camp data has been absent, making it challenging to apply findings from one country to another. Therefore, this study presents visual acuity data collected across 17 low- and middle-income countries (LMICs) by Vision Care, an international blindness relief organization that has operated over 300 short-term cataract camps since 2002.\u003c/p\u003e \u003cp\u003eThe goal of the study is threefold. First, to assess the correlation of the visual acuity and known country-level socioeconomic factors including Gross Domestic Product (GDP), Human Development Index (HDI), and Cataract Surgical Rate (CSR). Second, to assess its correlation to existing ophthalmologist workforce in each country. Third, to assess the differences in cataract surgery outcomes based on the type of surgical technique utilized.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003e This study was conducted in accordance with the tenets of the Declaration of Helsinki and was exempt from the institutional review board at Oregon Health and Science University.\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy Population\u003c/h2\u003e \u003cp\u003eThis observational study utilized de-identified data from Vision Care. The patients underwent cataract surgery between 2013 and 2023. The information used for analysis included the date of surgery, age, sex, type of surgical technique, preoperative visual acuity, postoperative visual acuity, and the country in which the surgery was performed. Uncorrected visual acuities (UCVA) were measured on ordinal scales such as no light perception (LP-), light perception (LP+), count fingers (CF), or hand motion (HM) at varying distances, or on Snellen scales on Snellen chart, a number chart, or a tumbling E chart.\u003c/p\u003e \u003cp\u003eOnly cataract extraction with intraocular lens (IOL) implant cases were included in the analysis. Cases with additional surgical treatments were excluded. For example, pterygium surgery, IOL exchange, IOL repositioning that may or may not have been paired with cataract extraction were excluded.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eCataract Camp Settings\u003c/h3\u003e\n\u003cp\u003eThe cataract camps were carried out in areas where Vision Care was invited by the local government. This study reflects cataract camps in the following countries: Bangladesh, Cambodia, China, Kyrgyzstan, Mauritania, Mongolia, Morocco, Mozambique, Nigeria, Pakistan, Peru, Sri Lanka, Tanzania, Uganda, Uzbekistan, Vanuatu, and Vietnam. In each camp, locally available equipment was used, and unavailable equipment was brought in via air transportation.\u003c/p\u003e \u003cp\u003eCamp participants were trained volunteers or Vision Care staff, with each camp having a unique set of members with a few returning volunteers. Surgical type was determined by the operating surgeon following a slit lamp exam. Individual IOL calculation and intraocular pressure (IOP) measurement were performed preoperatively. In general, extracapsular cataract extraction (ECCE) in a manual small incision cataract surgery (MSICS) fashion was preferred for dense and mature cataracts. Phacoemulsification was preferred if the cataract was deemed soft. The operating ophthalmologists were trained in the United States or South Korea, with a few local ophthalmologists operating under direct supervision of experienced surgeons. Operated patients were followed up the morning after the surgery and again on the last day of the camp for a second evaluation. During the one-week camp period, surgeries were performed Monday through Thursday, and Friday was dedicated to emergency cases and final follow-ups.\u003c/p\u003e\n\u003ch3\u003eSocioeconomic Factors\u003c/h3\u003e\n\u003cp\u003eThis study used country GDP per capita in 2021 constant international dollars with the purchasing power parity (PPP) calculations to adjust for economic inflation and account for differences in cost of living [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. The HDI summarizes the following four dimensions of socioeconomic factors: life expectancy, mean years of schooling, expected years of schooling, and gross national income (GNI) per capita [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. The CSR reports the number of cataract surgeries performed per million populations in a year [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. The number of ophthalmologists and the number of ophthalmologists performing cataract surgery per capita by country were obtained from a study published in 2020 by Resnikoff and colleagues [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e].\u003c/p\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eStatistical Analysis\u003c/h2\u003e \u003cp\u003eThe visual acuity data were converted into a LogMAR scale for ease of comparison. Snellen values were converted using the formula below:\u003c/p\u003e \u003cp\u003eLogMAR UCVA\u0026thinsp;=\u0026thinsp;\u0026minus;\u0026thinsp;1\u0026lowast;\u0026#119897;\u0026#119900;\u0026#119892;10(Fraction as a Decimal)\u003c/p\u003e \u003cp\u003eVisual acuities measured by various distances of hand motion (HM) and count finger (CF) were converted to LogMAR UCVA using methods previously described,using the mean distal interphalangeal (DIP) joint width, including inter-digit spaces, of 86.07mm [\u003cspan additionalcitationids=\"CR17\" citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eTo assess for changes in LogMAR UCVA between pre-operation and one, two, three, or four days post-operation, four paired Wilcoxon tests were conducted. Bonferroni corrections were applied to p-values.\u003c/p\u003e \u003cp\u003eMultivariable mixed-effects linear regression models were used to assess for the change in LogMAR UCVA over the first four days after surgery, accounting for age and sex, both overall as well as within each country. Similar models were used to assess for interactions between the change in LogMAR UCVA over the first four days after surgery, accounting for patient age and sex, and the following variables: surgery type, GDP PPP per capita, HDI, CSR, number of ophthalmologists per capita, and number of ophthalmologists per capita performing cataract surgery. After accounting for GDP PPP, the interactions between number of ophthalmologists, number of ophthalmologists performing cataract surgery, and HDI were also assessed.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eData was collected on 4120 eyes from 4110 patients from 52 cataract camps held between February 2013 and November 2023. Ages ranged from 3 to 109 years, with a mean of 66\u0026middot;9 years (Table 1). 55\u0026middot;2% of patients were female. 78\u0026middot;9% of patients underwent phacoemulsification, 20\u0026middot;6% underwent ECCE, and 0\u0026middot;4% underwent intracapsular cataract extraction (ICCE). Cataract operations were performed in 17 countries: Bangladesh, Cambodia, China, Kyrgyzstan, Mauritania, Mongolia, Morocco, Mozambique, Nigeria, Pakistan, Peru, Sri Lanka, Tanzania, Uganda, Uzbekistan, Vanuatu, and Vietnam. Most data were reported from China (15\u0026middot;9%), Morocco (15\u0026middot;6%), Tanzania (8\u0026middot;1%), Kyrgyzstan (8%), or Uzbekistan (7\u0026middot;7%). Only 1\u0026middot;2% of data were from Sri Lanka.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 1: Patient demographics.\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"324\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003eN = 4,110\u003cem\u003e\u003csup\u003e1\u003c/sup\u003e\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAge (years)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e66\u0026middot;9 (3\u0026middot;0, 109\u0026middot;0)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u003cem\u003e(Missing)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSex\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Female\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e2,269 (55%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Male\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e1,840 (45%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u003cem\u003e(Missing)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eOperation Type\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; ECCE\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e847 (21%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; ICCE\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e15 (0\u0026middot;4%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Phacoemulsification\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e3,243 (79%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u003cem\u003e(Missing)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCountry\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Bangladesh\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e186 (4\u0026middot;5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Cambodia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e97 (2\u0026middot;4%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; China\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e654 (16%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Kyrgyzstan\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e330 (8\u0026middot;0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Mauritania\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e180 (4\u0026middot;4%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Mongolia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e68 (1\u0026middot;7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Morocco\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e643 (16%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Mozambique\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e219 (5\u0026middot;3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Nigeria\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e101 (2\u0026middot;5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Pakistan\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e300 (7\u0026middot;3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Peru\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e56 (1\u0026middot;4%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Sri Lanka\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e49 (1\u0026middot;2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Tanzania\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e332 (8\u0026middot;1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Uganda\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e232 (5\u0026middot;6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Uzbekistan\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e317 (7\u0026middot;7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Vanuatu\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e53 (1\u0026middot;3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Vietnam\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 162px;\"\u003e\n \u003cp\u003e293 (7\u0026middot;1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 324px;\"\u003e\n \u003cp\u003e\u003cem\u003e\u003csup\u003e1\u003c/sup\u003e\u003c/em\u003e Mean (Min, Max); n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003ePre-Operative Visual Acuity\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePreoperative visual acuities were available for 3976 surgeries from 3955 eyes from 3945 patients. Among the 3976 surgeries with documented preoperative visual acuities, 3060 (77%) presented with a visual acuity of 20/200 or worse. As compared to ECCE, phacoemulsification eyes had significantly lower preoperative logMAR UCVA by an average of 0\u0026middot;834 units (p \u0026lt; 0\u0026middot;0001).\u003c/p\u003e\n\u003cp\u003eThere was a significant association between preoperative logMAR UCVA and GDP PPP per capita (p \u0026lt; 0\u0026middot;0001), with preoperative logMAR UCVA decreasing by an average of 0\u0026middot;028 units for every 1,000-unit increase in GDP PPP per capita (95% CI: 0\u0026middot;022 to 0\u0026middot;033). There was a significant association between preoperative logMAR UCVA and HDI (p \u0026lt; 0\u0026middot;0001), with preoperative logMAR UCVA decreasing by an average of 0\u0026middot;9 units for every 1-unit increase in HDI (95% CI: 0\u0026middot;62 to 1\u0026middot;18). There was a significant association between preoperative logMAR UCVA and CSR per million (p = 0\u0026middot;0002), with preoperative logMAR UCVA decreasing by an average of 0\u0026middot;073 units for every 1,000-unit increase in CSR per million (95% CI: 0\u0026middot;035 to 0\u0026middot;11). There was a significant association between preoperative logMAR UCVA and the number of ophthalmologists per million citizens performing cataract surgery (p \u0026lt; 0\u0026middot;0001), with preoperative logMAR UCVA decreasing by an average of 0\u0026middot;053 units for every 1 additional ophthalmologist per million citizens performing cataract surgery (95% CI: 0\u0026middot;045 to 0\u0026middot;061).\u003c/p\u003e\n\u003cp\u003eThere was not a significant association between preoperative logMAR UCVA and the number of ophthalmologists per million citizens (p = 0\u0026middot;2741).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eChanges in Visual Acuity\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe mean LogMAR UCVA for all patients changed from 1\u0026middot;66 preoperatively to 0\u0026middot;964 one day postoperatively, 0\u0026middot;864 at two days, 0\u0026middot;805 at three days, and 0\u0026middot;79 at four days. There was a significant improvement from preoperative visual acuity at one day (p \u0026lt; 0\u0026middot;0001), two days (p \u0026lt; 0\u0026middot;0001), three days (p \u0026lt; 0\u0026middot;0001), and four days (p \u0026lt; 0\u0026middot;0001) postoperatively. (Table 2).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2: Summary of LogMAR UCVA preoperation and one, two, three, or four days postoperation.\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"617\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 56px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePreoperation\u003c/strong\u003e\u003cbr\u003eN = 3,955\u003cem\u003e\u003csup\u003e1\u003c/sup\u003e\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eOne Day\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003ePostoperation\u003c/strong\u003e\u003cbr\u003eN = 3,591\u003cem\u003e\u003csup\u003e1\u003c/sup\u003e\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTwo Days Postoperation\u003c/strong\u003e\u003cbr\u003eN = 798\u003cem\u003e\u003csup\u003e1\u003c/sup\u003e\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eThree Days Postoperation\u003c/strong\u003e\u003cbr\u003eN = 741\u003cem\u003e\u003csup\u003e1\u003c/sup\u003e\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eFour Days Postoperation\u003c/strong\u003e\u003cbr\u003eN = 483\u003cem\u003e\u003csup\u003e1\u003c/sup\u003e\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 56px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eLogMAR UCVA\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003e1\u0026middot;657\u003c/p\u003e\n \u003cp\u003e(0\u0026middot;000, 3\u0026middot;079)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003e0\u0026middot;962\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(-0\u0026middot;140, 3\u0026middot;079)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003e0\u0026middot;865\u003c/p\u003e\n \u003cp\u003e(-0\u0026middot;176, 3\u0026middot;079)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003e0\u0026middot;807\u003c/p\u003e\n \u003cp\u003e(-0\u0026middot;523, 3\u0026middot;000)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003e0\u0026middot;789\u003c/p\u003e\n \u003cp\u003e(-0\u0026middot;806, 3\u0026middot;000)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 56px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMedian decrease in LogMAR UCVA\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003e\u0026middot;\u0026middot;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003e0\u0026middot;650\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003e0\u0026middot;875\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003e0\u0026middot;835\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003e0\u0026middot;778\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 56px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP-Value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003e\u0026middot;\u0026middot;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003e\u0026lt; 0\u0026middot;0001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003e\u0026lt; 0\u0026middot;0001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003e\u0026lt; 0\u0026middot;0001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003e\u0026lt; 0\u0026middot;0001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\" style=\"width: 617px;\"\u003e\n \u003cp\u003e\u003cem\u003e\u003csup\u003e1\u003c/sup\u003e\u003c/em\u003e Mean (Min, Max)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eThere was a significant association between calculated LogMAR UCVA and days post-operation (p \u0026lt; 0\u0026middot;0001; conditional R\u003csup\u003e2\u003c/sup\u003e = 0.42), with LogMAR UCVA decreasing by an average of 0\u0026middot;286 units per day post-operation (95% CI: 0\u0026middot;274 to 0\u0026middot;298; Figure A1). This significant decrease in LogMAR UCVA per day was consistent across all 17 countries (p \u0026lt; 0\u0026middot;001).\u003c/p\u003e\n\u003cp\u003eAfter accounting for age and sex, there was a significant interaction between the change in logMAR UCVA per day after surgery and preoperative logMAR UCVA (p \u0026lt; 0\u0026middot;0001), with logMAR UCVA decreasing by an additional\u0026nbsp;0\u0026middot;054 units for every 1 additional unit in preoperative logMAR UCVA\u0026nbsp;(95% CI: 0\u0026middot;041 to 0\u0026middot;067 additional units).\u003c/p\u003e\n\u003cp\u003eAs compared to patients who underwent phacoemulsification, patients who underwent ECCE exhibited a greater decrease in LogMAR UCVA per day (p \u0026lt; 0\u0026middot;0001), decreasing by 0\u0026middot;175 additional units per day (95% CI: 0\u0026middot;146 to 0\u0026middot;205; Figure 1).\u003c/p\u003e\n\u003cp\u003eThe decrease in LogMAR UCVA per day was significantly greater in countries with fewer ophthalmologists per million performing cataract surgery (p \u0026lt; 0\u0026middot;0001). Between the first quartile of number of ophthalmologists performing cataract surgery per million citizens of 1\u0026middot;7 and the third quartile of 9\u0026middot;9, the average decrease in LogMAR UCVA per day post-operation decreased from 0\u0026middot;352 to 0\u0026middot;274 units per day. This association remained after accounting for GDP PPP per capita (p = 0\u0026middot;0024).\u003c/p\u003e\n\u003cp\u003eThe decrease in LogMAR UCVA per day was not significantly associated with the ophthalmologists per million (p = 0\u0026middot;7462), HDI (p = 0\u0026middot;716), CSR per million (p = 0\u0026middot;7532), or GDP PPP per capita (p = 0\u0026middot;8059).\u003cbr\u003e\u0026nbsp;\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn this study, we reported the outcomes of 52 cataract camps from 17 LMICs. Our global data demonstrates a highly significant and consistent improvement in visual acuity from day one through four (p\u0026thinsp;\u0026lt;\u0026thinsp;0\u0026middot;0001) after the surgery. This trend was universal across all countries in this study, suggesting a strong argument for the model\u0026rsquo;s replicability and generalizability.\u003c/p\u003e \u003cp\u003eWe found that the rate of improvement in vision was significantly higher in patients who presented with worse preoperative vision. This tells us that cataract surgery brings the most benefits to the population with the highest burden of unoperated, longstanding cataracts, which contribute to avoidable blindness in many LMICs. The rate of improvement was also significantly higher in those who underwent ECCE surgery than phacoemulsification. The observed faster initial recovery with the ECCE/MSICS method supports its use as a pragmatic approach in low-resource settings for treating severe cataracts, consistent with previous studies [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eContrary to expectations, broader national-level indicators, including total ophthalmologists per capita, HDI, CSR, and GDP PPP, were not significantly associated with the daily rate of visual recovery. (p\u0026thinsp;\u0026gt;\u0026thinsp;0\u0026middot;7 for all) This suggests that these short-term postoperative outcomes are more strongly influenced by individual-level factors, such as baseline UCVA and surgical type, rather than by macroeconomic context. This finding appears to contrast with prior reports on global disparities in visual impairment, which emphasized the importance of economic indicators in estimating healthcare access and visual outcomes [\u003cspan additionalcitationids=\"CR3\" citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. One possible explanation lies in the site selection process of Vision Care. The camp sites are typically chosen based on requests from local governments or partner organizations, selecting areas with higher demand for cataract surgery. As a result, the national socioeconomic indices used in this analysis may not accurately reflect the specific regions where Vision Care operates, particularly considering the substantial disparities in wealth and healthcare access within each country.\u003c/p\u003e \u003cp\u003eNotably, however, the daily rate of visual improvement was significantly higher in countries with the lowest density of local cataract surgeons (p\u0026thinsp;\u0026lt;\u0026thinsp;0\u0026middot;0001), a relationship that remained significant even after controlling for national GDP PPP (p\u0026thinsp;=\u0026thinsp;0\u0026middot;0024). This suggests that cataract camps are most impactful where local eye care infrastructure is the weakest, further supporting the role of cataract camp as an effective and essential mechanism for closing the growing treatment gap in socioeconomically vulnerable regions. The persistence of this association after controlling for GDP PPP emphasizes that the scarcity of trained surgeons, rather than general economic development, is the primary constraint that cataract camps are designed to overcome. This result is particularly relevant in the context of globally aging population and the subsequently increasing demand for eye health services including cataract surgery.\u003c/p\u003e \u003cp\u003e Given these results, our study strongly advocates the importance of training and incentivizing local ophthalmologists in LMICs to perform cataract surgery, with or without the aid of cataract camps. Organizations like Vision Care have been actively involved in equipping local eye care providers and ophthalmologists to expand vision screening and perform cataract surgeries. These educational initiatives can not only improve the efficiency of cataract camps but also strengthen local ophthalmologists by offering direct hands-on training from experienced surgeons. Given the marked shortage of ophthalmologists in LMICs, training competent eye care professionals who take on the challenge locally will be critical in achieving a sustainable eye care model [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThis study has several limitations inherent to the analysis of observational data from a mass campaign format. First, our visual acuity data is limited to uncorrected visual acuity (UCVA) and does not include best-corrected visual acuity (BCVA). While UCVA is a practical and relevant outcome for evaluating the functional success of cataract camps, it may not capture the full rehabilitative potential. Second, the follow-up period is limited to the duration of the camp, preventing an assessment of long-term surgical outcomes, stability of vision, or post-operative complication rates. Yet, previous studies have suggested that such short-term visual acuity is still a valuable quality control measure in areas with poor follow-up rates [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. Finally, the use of macro-level socioeconomic indicators may obscure heterogeneity within each country.\u003c/p\u003e \u003cp\u003eTo our knowledge, this study is the largest studies of multinational cataract camps, involving data from 17 LMICs and over four thousand patients. We conclude that cataract camps may yield the greatest impact in populations with the most severe cataracts and in countries facing the greatest shortage of local cataract surgeons. To tackle the growing global challenge of vision impairment, clinicians and policymakers must continue to support high-volume, targeted interventions like cataract camps while simultaneously focusing on building sustainable local surgical capacity.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eFunding source\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study involves the NEI P30 EY010572 core grant and an unrestricted grant from Research to Prevent Blindness to the Casey Eye Institute of Oregon Health and Science University. The authors have not been paid to write this article. The authors were not precluded from accessing data in the study and they accept responsibility to submit for publication.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAll authors had access to the data and had distinctive role in writing the manuscript.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e- Eunyoo Kim: conceptualization, data curation, investigation, methodology, resources, writing — original draft, writing — review \u0026amp; editing.\u003c/p\u003e\n\u003cp\u003e- Elizabeth White: Formal analysis, writing — original draft, writing — review \u0026amp; editing.\u003c/p\u003e\n\u003cp\u003e- Dongseok Choi: Formal analysis, writing — review \u0026amp; editing.\u003c/p\u003e\n\u003cp\u003e- Dong-wouk Park: conceptualization, methodology, project administration, resources, writing — original draft, writing — review \u0026amp; editing.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eGBD 2019 Blindness and Vision Impairment Collaborators, \u0026amp; Vision Loss Expert Group of the Global Burden of Disease Study. 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A Global View on Output and Outcomes of Cataract Surgery With National Indices of Socioeconomic Development. \u003cem\u003eInvest Ophthalmol Vis Sci\u003c/em\u003e 2017; \u003cstrong\u003e58\u003c/strong\u003e(9): 3669\u0026ndash;3676. doi:10.1167/iovs.17-21489\u003c/li\u003e\n \u003cli\u003eBurton MJ, Ramke J, Marques AP, et al. The Lancet Global Health Commission on Global Eye Health: vision beyond 2020. \u003cem\u003eLancet Glob Health\u003c/em\u003e 2021; \u003cstrong\u003e9\u003c/strong\u003e(4): e489\u0026ndash;e551. doi:10.1016/S2214-109X(20)30488-5\u003c/li\u003e\n \u003cli\u003eHan X, Zou M, Liu Z, et al. Time trends and heterogeneity in the disease burden of visual impairment due to cataract, 1990-2019: A global analysis. \u003cem\u003eFront Public Health\u003c/em\u003e 2023; \u003cstrong\u003e11\u003c/strong\u003e: 1140533. Published 2023 Apr 3. doi:10.3389/fpubh.2023.1140533\u003c/li\u003e\n \u003cli\u003eRamke J, Evans JR, Gilbert CE. Reducing inequity of cataract blindness and vision impairment is a global priority, but where is the evidence?. \u003cem\u003eBr J Ophthalmol\u003c/em\u003e 2018; \u003cstrong\u003e102\u003c/strong\u003e(9): 1179\u0026ndash;1181. doi:10.1136/bjophthalmol-2018-311985\u003c/li\u003e\n \u003cli\u003eSangameswaran RP, Verma GK, Raghavan N, Joseph J, Sivaprakasam M. Cataract surgery in mobile eye surgical unit: Safe and viable alternative. \u003cem\u003eIndian J Ophthalmol\u003c/em\u003e 2016; \u003cstrong\u003e64\u003c/strong\u003e(11): 835\u0026ndash;839. doi:10.4103/0301-4738.195599\u003c/li\u003e\n \u003cli\u003eMurthy GV, Sharma P. Cost analysis of eye camps and camp-based cataract surgery. \u003cem\u003eNatl Med J India\u003c/em\u003e 1994; \u003cstrong\u003e7\u003c/strong\u003e(3): 111\u0026ndash;114.\u003c/li\u003e\n \u003cli\u003eJavaloy J, Signes-Soler I, Moya T, Litila S. Cataract surgery in surgical camps: outcomes in a rural area of Cameroon. \u003cem\u003eInt Ophthalmol\u003c/em\u003e 2021; \u003cstrong\u003e41\u003c/strong\u003e(1): 283\u0026ndash;292. doi:10.1007/s10792-020-01580-5\u003c/li\u003e\n \u003cli\u003eBhatta S, Pant N, Thakur AK, Pant SR. Outcomes of Cataract Surgeries Performed in Makeshift Operating Rooms in Rural Camps, Compared to Hospital-based Surgeries in Nepal. \u003cem\u003eOphthalmic Epidemiology\u0026nbsp;\u003c/em\u003e2021; \u003cstrong\u003e29\u003c/strong\u003e(5): 566\u0026ndash;572. doi:10.1080/09286586.2021.1976805.\u003c/li\u003e\n \u003cli\u003eDanquah L, Kuper H, Eusebio C, et al. The long term impact of cataract surgery on quality of life, activities and poverty: results from a six year longitudinal study in Bangladesh and the Philippines. \u003cem\u003ePLoS One\u003c/em\u003e 2014; \u003cstrong\u003e9\u003c/strong\u003e(4): e94140. Published 2014 Apr 18. doi:10.1371/journal.pone.0094140\u003c/li\u003e\n \u003cli\u003eWorld Bank. GDP per capita, PPP (constant 2021 international $) [Internet]. World Bank Data; 2023 [cited 2025 Oct 22]. Available from: https://data.worldbank.org/indicator/NY.GDP.PCAP.PP.KD?end=2023\u0026amp;locations=BD-CN-KG-MR-MN-MA-MZ-NG-PK-PE-LK-TZ-UG-UZ-VN-VU\u0026amp;start=2014\u003c/li\u003e\n \u003cli\u003eUnited Nations Development Programme. \u003cem\u003eCountry Insights \u0026ndash; Human Development Reports Data Center\u003c/em\u003e [Internet]. [cited 2025 Oct 22]. Available from: https://hdr.undp.org/data-center/country-insights#/ranks\u003c/li\u003e\n \u003cli\u003eRaab World. Country Profiles [Internet]. [cited 2025 Oct 22]. Available from: https://www.raab.world/country-profiles\u003c/li\u003e\n \u003cli\u003eResnikoff S, Lansingh VC, Washburn L, et al. Estimated number of ophthalmologists worldwide (International Council of Ophthalmology update): will we meet the needs?. \u003cem\u003eBr J Ophthalmol\u003c/em\u003e 2020; \u003cstrong\u003e104\u003c/strong\u003e(4): 588\u0026ndash;592. doi:10.1136/bjophthalmol-2019-314336\u003c/li\u003e\n \u003cli\u003eSchulze-Bonsel K, Feltgen N, Burau H, Hansen L, Bach M. Visual acuities \u0026quot;hand motion\u0026quot; and \u0026quot;counting fingers\u0026quot; can be quantified with the freiburg visual acuity test. \u003cem\u003eInvest Ophthalmol Vis Sci\u003c/em\u003e 2006; \u003cstrong\u003e47\u003c/strong\u003e(3): 1236\u0026ndash;1240. doi:10.1167/iovs.05-0981\u003c/li\u003e\n \u003cli\u003eLange C, Feltgen N, Junker B, Schulze-Bonsel K, Bach M. Resolving the clinical acuity categories \u0026quot;hand motion\u0026quot; and \u0026quot;counting fingers\u0026quot; using the Freiburg Visual Acuity Test (FrACT). \u003cem\u003eGraefes Arch Clin Exp Ophthalmol\u003c/em\u003e 2009; \u003cstrong\u003e247\u003c/strong\u003e(1): 137\u0026ndash;142. doi:10.1007/s00417-008-0926-0\u003c/li\u003e\n \u003cli\u003eKaranjia R, Hwang TJ, Chen AF, et al. Correcting Finger Counting to Snellen Acuity. \u003cem\u003eNeuroophthalmology\u003c/em\u003e 2016; \u003cstrong\u003e40\u003c/strong\u003e(5): 219\u0026ndash;221. Published 2016 Aug 22. doi:10.1080/01658107.2016.1209221\u003c/li\u003e\n \u003cli\u003eRuit S, Tabin G, Chang D, et al. A prospective randomized clinical trial of phacoemulsification vs manual sutureless small-incision extracapsular cataract surgery in Nepal. \u003cem\u003eAm J Ophthalmol\u003c/em\u003e 2007; \u003cstrong\u003e143\u003c/strong\u003e(1): 32\u0026ndash;38. doi:10.1016/j.ajo.2006.07.023\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eResnikoff S, Felch W, Gauthier TM, Spivey B. The number of ophthalmologists in practice and training worldwide: a growing gap despite more than 200,000 practitioners. \u003cem\u003eBr J Ophthalmol\u003c/em\u003e 2012; \u003cstrong\u003e96\u003c/strong\u003e(6): 783\u0026ndash;787. doi:10.1136/bjophthalmol-2011-301378\u003c/li\u003e\n \u003cli\u003eAliyu H, Mustak H, Cook C. Using the Postoperative Visual Acuity to Monitor the Quality of Cataract Surgery: Does the Day One Visual Acuity following Cataract Surgery Correlate with the Final Visual Acuity?. \u003cem\u003eMiddle East Afr J Ophthalmol\u003c/em\u003e 2017; \u003cstrong\u003e24\u003c/strong\u003e(2): 91\u0026ndash;93. doi:10.4103/meajo.MEAJO_279_16\u003c/li\u003e\n \u003cli\u003eKurian DE, Amritanand A, Mathew M, Keziah M, Rebekah G. Correlation between visual acuity at discharge and on final follow-up in patients undergoing manual small incision cataract surgery. \u003cem\u003eIndian J Ophthalmol\u003c/em\u003e 2021; \u003cstrong\u003e69\u003c/strong\u003e(3): 586\u0026ndash;589. doi:10.4103/ijo.IJO_986_20\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"international-ophthalmology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"inte","sideBox":"Learn more about [International Ophthalmology](https://www.springer.com/journal/10792)","snPcode":"10792","submissionUrl":"https://submission.nature.com/new-submission/10792/3","title":"International Ophthalmology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Cataracts, world blindness, socioeconomic disparity, global health, cataract camp, blindness prevention","lastPublishedDoi":"10.21203/rs.3.rs-8437303/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8437303/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cb\u003eBackground\u003c/b\u003e\u003c/p\u003e \u003cp\u003eCataracts are the leading cause of reversible blindness worldwide. Though temporary and resource-intensive, cataract camps provide large-scale treatment of the condition. This study sought to determine socioeconomic factors that affect short-term improvements in visual acuity observed in cataract camps across 17 countries.\u003c/p\u003e\u003cp\u003e\u003cb\u003eMethods\u003c/b\u003e\u003c/p\u003e \u003cp\u003eThis observational study represents 52 camps in 17 low- and middle-income countries. Mixed-effects linear regression models were used to analyze associations between changes in LogMAR score of uncorrected visual acuity (UCVA) one to four days post-operation and socioeconomic factors including per capita GDP, Human Development Index, Cataract Surgical Rate, and density of in-country ophthalmologists.\u003c/p\u003e\u003cp\u003e\u003cb\u003eFindings\u003c/b\u003e\u003c/p\u003e \u003cp\u003eAmong 4110 patients, after accounting for age and sex, LogMAR UCVA significantly decreased over the first four days postoperatively (p\u0026thinsp;\u0026lt;\u0026thinsp;0\u0026middot;0001). This decrease was also associated with the number of ophthalmologists per million performing cataract surgery (p\u0026thinsp;=\u0026thinsp;0\u0026middot;0227). Patients who underwent extracapsular cataract extraction (ECCE) exhibited a greater decrease in LogMAR UCVA per day post-op (p\u0026thinsp;\u0026lt;\u0026thinsp;0\u0026middot;0001). Per capita GDP was not significantly associated with the change in LogMAR UCVA per day post-op.\u003c/p\u003e\u003cp\u003e\u003cb\u003eInterpretation\u003c/b\u003e\u003c/p\u003e \u003cp\u003eOur analyses suggest that cataract camps in areas with fewer ophthalmologists performing cataract surgery and ECCE surgeries correlated with the most improvement in vision. Targeting such populations and training local ophthalmologists to perform ECCE surgery may yield a higher impact in low-resource settings with a high burden of cataract-induced blindness.\u003c/p\u003e","manuscriptTitle":"Socioeconomic Factors Affecting Visual Acuity in Cataract Camps","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-01-16 08:57:08","doi":"10.21203/rs.3.rs-8437303/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-03-04T11:29:07+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-03T20:27:54+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-01-15T10:48:55+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"187967548402299338737605160214885120926","date":"2026-01-14T17:17:24+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"131333724237412885352563655032621247614","date":"2026-01-14T12:39:15+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-01-12T10:05:55+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-12-24T13:42:57+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-12-24T13:41:40+00:00","index":"","fulltext":""},{"type":"submitted","content":"International Ophthalmology","date":"2025-12-23T22:05:17+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"international-ophthalmology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"inte","sideBox":"Learn more about [International Ophthalmology](https://www.springer.com/journal/10792)","snPcode":"10792","submissionUrl":"https://submission.nature.com/new-submission/10792/3","title":"International Ophthalmology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"db331224-b6ed-4847-8c0f-3cdf30d782ea","owner":[],"postedDate":"January 16th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2026-04-13T16:05:18+00:00","versionOfRecord":{"articleIdentity":"rs-8437303","link":"https://doi.org/10.1007/s10792-026-04063-1","journal":{"identity":"international-ophthalmology","isVorOnly":false,"title":"International Ophthalmology"},"publishedOn":"2026-04-06 15:58:04","publishedOnDateReadable":"April 6th, 2026"},"versionCreatedAt":"2026-01-16 08:57:08","video":"","vorDoi":"10.1007/s10792-026-04063-1","vorDoiUrl":"https://doi.org/10.1007/s10792-026-04063-1","workflowStages":[]},"version":"v1","identity":"rs-8437303","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8437303","identity":"rs-8437303","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}