Cost and Outcomes of Follow-up After Cataract Surgery in Low- and Middle-Income Countries (2024)

Key Points

Question Are interventions to increase low rates of follow-up after cataract surgery in low- and middle-income countries cost-effective?

Findings In this cohort of 2316 patients who attended follow-up after cataract surgery in 8 countries in Asia, Africa, and Latin America, the maximum proportions whose visual acuity might improve with glasses or necessary treatment after surgery and the corresponding incremental cost of improving visual acuity in 1 patient were increased from no follow-up to spontaneous follow-up. A telephone intervention and transportation subsidies to increase follow-up rates were not cost-effective.

Meaning Telephone calls or transport subsidies to increase follow-up in low- and middle-income countries may not be cost-effective; instead, patients should be reminded at the time of surgery to return for follow-up.

Importance Some experts recommend increasing low rates of follow-up after cataract surgery in low- and middle-income countries using various interventions. However, little is known about the cost and effect of such interventions.

Objective To examine whether promoting follow-up after cataract surgery creates economic value.

Design, Setting, and Participants The Prospective Review of Early Cataract Outcomes and Grading (PRECOG) is a cohort study with data from patients undergoing cataract surgery from January 19, 2010, to April 18, 2012. Final follow-up was completed on August 10, 2012. Data were collected before surgery, at discharge, and at follow-up at least 40 days after surgery from 27 centers in 8 countries in Asia, Africa, and Latin America. Each center enrolled 40 to 120 consecutive patients undergoing cataract surgery. If patients did not return to the hospital for the follow-up visit, hospitals could use telephone calls or transportation subsidies to increase follow-up rate. Data were analyzed from December 2013 to January 2016.

Main Outcomes and Measures Cost of interventions (telephone calls and transportation subsidies) to increase follow-up at least 40 days after surgery, visual acuity (VA) in the eye undergoing cataract surgery, presence of complications, patient and facility costs per visit, and willingness to pay for treatment or glasses if needed. The maximum incremental cost of improving VA in 1 patient (incremental cost-effect ratio [ICER]) was calculated for spontaneous follow-up (compared with no follow-up) and follow-up with the telephone and transportation interventions. Expected ICERs were estimated including only those patients willing to pay.

Results Among 2487 patients (1068 men [42.9%]; 1405 women [56.5%]; 14 missing [0.6%]; mean [SD] age, 68.4 [11.3] years), 2316 (93.1%) received follow-up, of whom 369 (16.0%) were seen in an outside facility or home and were in the cost-effectiveness analysis as unable to follow up. A grand mean (a mean of means of the different countries) of 56.3% of patients needed glasses, of whom 56.9% were willing to pay, and 1.6% had treatable complications, of whom 39.4% were willing to pay. Maximum proportions with improved VA (and corresponding ICERs) were 0.08 for no follow-up, 0.45 ($151.56) for spontaneous follow-up, 0.53 ($164.46) for a telephone intervention, and 0.53 ($133.07) for a transportation intervention. These results were most sensitive to the cost of follow-up. Expected proportions (ICERs) were 0.08, 0.27 ($232.69), 0.30 ($456.22), and 0.30 ($206.47), respectively.

Conclusions and Relevance Most patients benefiting from follow-up after cataract surgery returned spontaneously when requested at discharge. Use of telephone calls or transportation subsidies to increase follow-up in low- and middle-income countries may not be cost-effective.

Cataract is the leading cause of blindness and visual impairment in lower- and middle-income countries (LMICs) and is responsible for the most disability-adjusted life-years due to visual loss globally.^1,2 Cataract surgery often achieves excellent visual outcomes with low rates of complication.^3,4 However, in LMICs, cataract surgical coverage is often low, and visual outcomes may be poor,^1,5-8 especially owing to operative complications and uncorrected refractive errors, both of which require postoperative follow-up for diagnosis and treatment.^4,8-12 Unfortunately, even short-term (<6 weeks) follow-up rates after cataract surgery are less than 50% in many regions in LMICs and may fall below 30%.^13,14

Investigators^14-17 have suggested that improvement of postoperative follow-up is critical to enhancing cataract surgical outcomes. A previous report,¹⁴ based on data from 40 centers in LMICs in the Prospective Review of Early Cataract Outcomes and Grading (PRECOG) study, found that early assessment of vision after cataract surgery is an accurate indicator of surgical quality where follow-up rates are low. Although postoperative follow-up may not be required to assess outcome quality, understanding whether follow-up contributes to improving visual outcomes and whether patients who would benefit from follow-up are among those returning spontaneously is important. We herein present analyses from PRECOG data examining whether promoting follow-up after cataract surgery with telephone calls or transportation subsidies creates economic value from the perspective of society or the patient.

The methods for the PRECOG study have been reported in detail¹⁴ and are summarized herein. Hospitals from Asia, Latin America, and Africa were solicited to participate through international nongovernmental organizations focused on eye health. The protocol for the PRECOG study was approved by the institutional review board at the coordinating center (Zhongshan Ophthalmic Center, Guangzhou, China) and those of other participating organizations (listed at the end of the article). All participants provided written informed consent, and the principles of the Declaration of Helsinki were followed throughout.

Each hospital enrolled 40 to 120 consecutive patients 30 years or older undergoing surgery for visually significant adult-onset cataract. Patients could have any level of visual acuity (VA) in the eye undergoing surgery deemed appropriate for surgery by local physicians but could not have apparent preoperative ocular comorbidities.

All patients underwent preoperative ocular examinations by an ophthalmologist or an ophthalmic clinical officer using a slitlamp with dilation of the pupil. Data reported for each patient included demographic information, history of cataract surgery, uncorrected VA (UCVA) and best-corrected VA (BCVA) in both eyes, the presence of ocular comorbidities, and biometric measurements to determine the power of the intraocular lens for surgery.

The VA for each eye was assessed at each hospital using its usual charts (tumbling E in all cases) at the recommended distance, usually 4.0 m. After correctly identifying the direction of most of the optotypes on the uppermost line (usually corresponding to VA of 3/60), patients moved to the next and successively lower lines. The lowest line in which most of the optoptypes was correctly read was recorded as the patient’s VA.

The early postoperative examination was completed within 72 hours after surgery, at hospital discharge in most centers. Data recorded included UCVA and BCVA in the eye undergoing surgery and the intraoperative or perioperative complications. All participants were instructed to return for a final examination at least 40 days after surgery, with earlier visits at the discretion of the facility.

Final examinations were performed on all participants returning spontaneously to the hospital at least 40 days after surgery. Forty days after enrolling the final patient, a facility could use telephone calls alone or in combination with transportation subsidies to encourage unexamined participants to return. At least 3 months after enrolling the final patient, facilities began home visits for unexamined patients, with a target of examining at least 90% of enrollees. Clinics maintained a log recording whether a patient had returned spontaneously or after a study intervention or was examined at home.

The final examination included pupil dilation and slitlamp examination by an ophthalmologist. The UCVA and BCVA in the eye undergoing surgery and the presence and type of postoperative complications were collected. Complications were categorized by the principal investigator (N.C.) as treatable by medication, treatable by incisional surgery or laser therapy, or not treatable.

Patients whose distance VA in the eye undergoing surgery improved by at least 2 lines with refraction were defined as needing glasses. Patients were asked if they had been offered glasses at a previous visit and for what price; if not, whether they would accept glasses; and if so, the price they were willing to pay (selected from among 4 locally relevant options). Patients who had visually significant operative complications amenable to medical or surgical treatment were asked whether they would accept treatment, and, if so, to select the amount they were willing to pay.

All patients were asked to estimate their total cost for a return hospital visit, including transportation, food, lodging, and lost income for themselves and any accompanying persons. Facilities provided information on their total cost of a postoperative visit (including labor and facility costs, such as electricity and consumables) and cost per patient of the interventions they had selected to improve follow-up. Hospitals additionally provided the costs of an average pair and the cheapest pair of glasses available at the facility. Consensus fees for typical postoperative medical and surgical interventions (eg, anterior chamber washout, laser treatment) were set for each region based on discussions with partners. Total (hospital + patient) costs increased when telephone calls were made but not with transportation subsidies because this aid could be subtracted from patient costs.

All VA data were converted to logMAR units. Counting fingers, hand movements, light perception, and no light perception were assigned logMAR values of 2.0, 2.3, 2.5, and 2.7, respectively. The estimated expected effect of the follow-up visit on VA was calculated as the difference between UCVA and BCVA for patients needing glasses, or half the number of lines from the UCVA to normal VA (6/6 = 0.0 on the logMAR scale) for patients with treatable complications. For example, a patient with UCVA of 6/60 (logMAR scale, 1.0) and a treatable complication was estimated to improve by 5 lines, because 10 lines are between 1.0 and 0.0 on the logMAR scale. These analyses were performed using STATA Statistical Software (release 12.0; StataCorp). Mean willingness to pay for glasses was calculated among those needing glasses using the following equation:

[(No. of Patients Who Bought Glasses × Mean Price Paid) + (No. of Patients Without Glasses × Mean Price Willing to Pay)]/No. of Patients Who Need Glasses

Cost-effectiveness analyses were performed using a decision tree to analyze the following 4 strategies to promote patient follow-up: (1) no follow-up (assuming no patients were examined at ≥40 days postoperatively); (2) patients return spontaneously after discharge for examination, but no interventions were performed to promote follow-up; (3) patients return spontaneously plus receive a telephone reminder for patients not returning by 40 days; and (4) patients return spontaneously plus receive a telephone reminder plus transportation subsidies for patients not returning by 40 days. Home visits were not included in analyses because these are not considered sustainable in routine clinical practice.

A positive patient outcome of follow-up was defined as having at least 2 lines of improvement in VA in the eye undergoing surgery if glasses or treatment was needed after the visit, as calculated above. In the sensitivity analysis, only those who would pay for care were included (ie, expected effect), whereas in the analysis of maximum possible effect, we assumed that all patients needing glasses, surgery, or medicines accepted them (Figure).

Analyses were performed under the following assumptions. For strategy 1 (no follow-up after 40 days), no treatment of complications would occur, and an estimated 14% of patients needing glasses would purchase them elsewhere without the costs of the hospital visit. For strategies 2, 3, and 4, an estimated 11% of those who did not return for follow-up would purchase glasses. These figures are based on studies of spectacle purchase among patients with cataract in China¹⁸ and Iran.¹⁹

For those with a complication requiring surgery, the mean price of surgery was added plus the cost of 2 extra visits and the consensus price of postoperative medication. Owing to the relatively low prevalence of complications requiring treatment (mean of means, 1.6% in total), global proportions of the intervention type required (incisional surgery, 39.4%; laser treatment, 15.2%; and medications, 45.5%) were applied for calculations in each region, to avoid unstable estimates. Owing to incomplete patient responses on the price they were willing to pay for treatment (with no responding patients willing to pay for surgery), we assumed as a lower end for our sensitivity analysis that only those patients with complications treatable with medication would be willing to pay and that all surgical therapy would be refused.

For all cost-effectiveness analyses, grand means (means of means of the different countries) were used to prevent countries with more participants from unduly influencing results. All costs were converted to international dollars, defined as the amount of a currency required to purchase the same quantity of goods and services as US $1.00 could purchase in the United States, according to the purchasing power parity index on World Bank website.²⁰ Because follow-up visits occurred during less than 1 year, no discounting was used. The incremental cost-effectiveness ratio (ICER) was used to assess the cost-effectiveness of each strategy compared with the previous one (eg, spontaneous follow-up compared with no follow-up). The ICER was defined by the cost difference between 2 interventions, divided by the difference in their effect, representing the mean incremental cost for 1 improved patient. All cost-effectiveness analyses were performed using TreeAge Pro (version 2011; TreeAge Software, Inc).

Twenty-seven hospitals in 8 countries participated, including 14 in China, 5 in India, 2 in Eritrea, 2 in Mexico, and 1 each in Vietnam, Ecuador, Guatemala, and Paraguay (eTable in the Supplement). Median annual cataract surgical volume was 1820 (range, 42-91 759); 17 of 27 hospitals (63.0%) were public; and 11 of 27 (40.7%) were rural. Cost and follow-up data were available on 2487 patients (1068 men [42.9%]; 1405 women [56.5%]; 14 missing [0.6%]; mean [SD] age, 68.4 [11.3] years), of whom 1177 (47.4%) were older than 70 years.

The follow-up visit at least 40 days after surgery was completed for 2316 patients (93.1%). Among these, 1201 (51.9%) returned spontaneously, 708 (30.6%) after receiving interventions (telephone calls or transportation subsidies), and 369 (15.9%) were examined at home or a local facility. For surgical data, 1769 (71.1%) underwent small-incision cataract surgery, and 2022 (81.3%) had VA of 6/60 or worse in the operated-on eye before surgery and had substantial improvements in VA at the final postoperative visits (Table 1).

When using grand means, 75.3% of patients returned spontaneously and 56.0% needed glasses (Table 2). Of those needing glasses and returning to the hospital, 56.9% were willing to purchase them. The eFigure in the Supplement shows the VA of patients needing glasses. The global mean amount patients were willing to pay for glasses was $49.73, approximately the global mean price of the cheapest glasses. The total amount patients were willing to pay for glasses was $11.57 in Asia, $65.79 in Latin America, and $99.92 in Africa and fell below the mean price for inexpensive glasses in China, India, Paraguay, and Mexico (Table 3). Only a global mean of 1.6% of patients had treatable surgical complications. Of those returning to the hospital with a complication, a global mean of 39.4% would accept treatment. Table 2 also shows regional variations in the need for glasses (generally higher in Latin America and lower in Africa) and prevalence of complications.

Table 3 shows the costs of follow-up for patients and facilities and the local fees for treatments. The mean global cost of follow-up for patients was $50.50, with the lowest cost in Asia ($16.00) and highest in Latin America ($75.80). The global cost for treatment increased from medicine ($16.50) to laser treatment ($108.40) and incisional surgery ($217.00), although the cost of a typical pair of glasses ($109.00) exceeded that of laser treatment globally and for each region except Asia (glasses, $36.70; laser treatment, $103.00) (Table 3).

For the global and regional analyses, the greatest incremental effect in the proportion of patients achieving improved VA at follow-up ranged from 0.08 with no follow-up to 0.45 with spontaneous follow-up, with far smaller incremental effects from adding telephone calls or transportation support (overall proportion, 0.53 for both) (Table 4). Overall ICERs were $151.56, $164.46, and $133.05 for spontaneous follow-up alone, with the telephone intervention, and with the telephone plus transportation intervention, respectively. In our sensitivity analyses, we found that the ICER was most affected by changes in the cost of the follow-up visit (ie, the expected effect, accounting for willingness to pay for treatment). Interventions increased the proportion of patients with good VA by less than 0.01 (ICER for transportation subsidy intervention, $206.47) to 0.02 (ICER for telephone intervention, $456.22). Table 4 shows regional differences in these figures.

Cataract surgery is widely considered a cost-effective procedure in LMICs and rich countries,^21-24 but our studies suggest interventions to improve postoperative follow-up may not be. Cost-effectiveness of follow-up after other surgical procedures has been studied, with inconsistent results, suggesting that current follow-up regimens were appropriate in surgery for bladder cancer²⁵ but could be reduced after surgical resection of small cell lung cancer²⁶ and after adenotonsillectomy.²⁷ The present study, however, is the first of which we are aware to consider the cost-effectiveness of follow-up after cataract surgery in LMICs and, in particular, of methods to encourage patients to return to the clinic for postoperative follow-up when these rates are low.^13,14

The previous study using PRECOG data¹⁴ reported that VA immediately after cataract surgery was highly correlated with VA after 40 days, suggesting that, for purposes of quality assessment, follow-up of all patients is not needed. Other investigators^16,17 have suggested that postoperative follow-up is important for achieving optimal visual results and that facilities should invest in interventions to improve follow-up where the rates are low. However, our results suggest that the benefit of such interventions in terms of improved VA is limited.

In the present study, 52.7% of patients returned spontaneously to the hospital after 40 days (or 75.3% when a mean of means analysis was used to reduce the effect of China’s low 30% follow-up rate). Of these patients, nearly two-thirds would benefit from glasses (58.2%) or treatment of complications (1.5%) (Table 2). Approximately 60% of these patients would accept such sight-improving care. Those who returned only after telephone or transportation interventions were generally less willing to accept or pay for glasses and treatment. In other words, requesting patients at discharge to return for follow-up was effective because most of the patients benefiting from follow-up returned spontaneously, resulting in a low yield of interventions aiming to improve VA outcomes by further increasing follow-up rates.

Policymakers seeking to apply these results should be aware of regional differences in our results, however. The high global mean cost per patient improved from interventions such as telephone calls and transportation support may be compared with the ICER $52.05 (spontaneous + telephone interventions) in Asia (in the best case where all patients accepted postoperative care) because of the low cost of glasses and transportation there. Reduction in the cost of glasses and treatment of complications due to government, insurance, or other external subsidies or by other means, such as the use of ready-made spectacles,²⁸ would likely improve acceptance and thus the effect on VA and cost-effectiveness. However, other barriers besides cost, such as discomfort and lack of perceived need,²⁹ have been shown to reduce adult use of spectacles in LMICs.

Approximately one-third (27.9% in Africa) to almost two-thirds (64.8% in Latin America) of patients could benefit from glasses for residual postoperative refractive error. Because all hospitals used A-scans and keratometry for intraocular lens selection, these regional differences could reflect differing quality of the preoperative measurements, more limited stocks of intraocular lenses in some settings, or a tendency in some areas to aim for more myopic distance correction to improve uncorrected near VA. In addition, the definition of benefiting from glasses used herein was an improvement of 2 lines with correction in the eye undergoing surgery. Thus, we cannot infer that all or even most of these patients had impaired VA without glasses. A previous study¹⁸ reported that only 35% of patients with a similar 2-line improvement in VA in rural China would accept prescriptions, mostly owing to a lack of perceived need. Nonetheless, because only 5 of 40 hospitals in PRECOG (12.5%) reached the World Health Organization standard (80% of patients with uncorrected VA of 6/18 or better),¹⁴ investments in better biometric measurements and more complete stocks of intraocular lenses could improve this rate.

A common approach in assessment of cost-effectiveness is the use of cost per quality-adjusted life-year, where a year lived is weighed by the utility score, which represents the quality of life during that year.³⁰ Use of utility scores for vision research is controversial and the outcome is susceptible to cultural differences,³¹ suggesting that this approach is not well suited to the present study.

Strengths of our study included a high participation rate (>90%), a large sample size, and inclusion of a broad range of countries and hospital types. Furthermore, this is the first large study, to our knowledge, to collect data on direct patient and hospital costs for care after cataract surgery in LMICs. Limitations must also be acknowledged. Lack of data for near vision and the need for inexpensive reading glasses will lead to an underestimate of the cost-effectiveness of the postoperative care strategies, although such data are unlikely to have changed our conclusion about the limited visual effect of interventions to increase follow-up. Our use of the actual price paid for glasses to estimate willingness to pay for spectacles was likely an underestimate (patients might have been willing to pay more than they did). Finally, few data were available from participants on willingness to pay for treatment of complications because of the low prevalence (1.6%) of complications in our cohort. However, this low prevalence also meant that the influence of these figures on our conclusions was likely modest.

Follow-up should be encouraged at discharge after cataract surgery, but efforts to increase return rates where follow-up is poor do not create value for the patient or for society, largely because most patients who could benefit returned to the clinic spontaneously when requested at discharge to do so. Most important, this finding is robust to the inclusion of the patient’s willingness to pay for additional correction as a cost to the patient. Governmental authorities and not-for-profit foundations developing programs to reduce the burden of visual impairment by offering cataract surgery in LMICs can focus their scarce resources on case finding, patient education, and improvement of postoperative refractive error to reduce the need for prescription glasses.

Corresponding Author: Nathan Congdon, MD, MPH, Division of Preventive Ophthalmology, Zhongshan Ophthalmic Center, State Key Laboratory, Sun Yat-sen University, 54 S Xianlie St, Yuexiu District, Guangzhou, Guangdong 560010, China (ncongdon1@gmail.com).

Accepted for Publication: September 28, 2016.

Published Online: December 15, 2016. doi:10.1001/jamaophthalmol.2016.4735

Author Contributions: Drs Meltzer and Congdon had full access to all the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.

Study concept and design: Congdon, Kymes, Lansingh, Sisay, Mueller, Chan, Guan, Vuong.

Acquisition, analysis, or interpretation of data: Meltzer, Congdon, Yan, Lansingh, Chan, Jin, Karumanchi, Vuong, Rivera, McLeod-Omawale, He.

Drafting of the manuscript: Meltzer, Congdon, Sisay, Jin, Guan, Vuong.

Critical revision of the manuscript for important intellectual content: Congdon, Kymes, Yan, Lansingh, Mueller, Chan, Karumanchi, Rivera, McLeod-Omawale, He.

Statistical analysis: Meltzer, Kymes, Yan, Jin, Vuong.

Obtained funding: Congdon.

Administrative, technical, or material support: Lansingh, Sisay, Chan, Karumanchi, Guan, Rivera.

Study supervision: Congdon, Kymes, Karumanchi.

Conflict of Interest Disclosures: All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest and none were reported.

Funding/Support: This study was supported by the Fred Hollows Foundation; Orbis International; Helen Keller International; the International Agency for the Prevention of Blindness/VISION 2020 Latin American Regional Office; Aravind Eye Care System; and a Thousand Man Plan programme grant from the Chinese government (Dr Congdon).

Role of the Funder/Sponsor: The funding organizations had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; and preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

Additional Information: The PRECOG Study included the following investigators and Centers in China: D. Junping and H. Hong (Gao’an City People’s Hospital), D. Yonglei, A. Qiong (Xiushui County People’s Hospital), D. Yong, L. Gang (Xingguo County People’s Hospital), C. Guohua, Z. Ying (Ningdu County People’s Hospital), F. Yuhua, L. Xingxing (Wuning County People’s Hospital), L. Xiaofei, W. Wenbin (Wan’an County People’s Hospital), Z. Xuping (Yujiang County People’s Hospital), Z. Ming, X. Wei (Poyang County People’s Hospital), Z. Zhiqiang, H. Ting (Hengfeng County People’s Hospital), Z. Jianxiang, Z. Bin (Yushan County People’s Hospital), H. Jialin, C. Jiangbing (Dianbai County People’s Hospital), Z. Yitian (Dabu County People’s Hospital), Q. Zhihua (Dongyuan County Traditional Chinese Medicine Hospital), X. Honghui, F. Wei (Gaoyao City People’s Hospital), X. Zhongyu, L. Liyong (Jieyang City People’s Hospital), C. Jian, L. Lijun (Xinyi County Traditional Chinese Medicine Hospital), C. Shaona, Y. Tianman (Yangjiang Bright Eye Hospital), and C. Chunhui, Z. Baoqiang (Yangxi County People’s Hospital); in Eritrea: G. Mebrahtu, A. Tesfa, M. Zerom (Ministry of Health), N. Gebremicheal (Godaif Hospital), S. Khanthamaly, H. Gebregergis (Barentu Hospital), and S. Mustafa (Keren Hospital); in Ethiopia: D. Hailu, C. Abity, A. Gabre (cataract surgeons), D. Almaz, P. Shegitu, A. Abera (integrated eye-care workers) (Duramie, Areka, and Wolkitie Hospitals); in Vietnam: T. N. Quynh (Eye Hospital of Ninh Binh Province), D. K. Dung (Eye Centre of Ha Tinh Province), N. H. Le (Eye Hospital of Nghe An Province), T. T. P. Thu (Eye Hospital of Ho Chi Minh City), and N. X. Phuong (Centre of Social Disease Control of Yen Bai Province); in Mexico: D. Garcia, H. Silva (Instituto de la Visión Montemorelos), and C. G. Salazar, B. Lopez (Tabasco Instituto de la Visión); in Peru: J. Huaman (Instituto Regional de Oftalmología), C. Tasayco, A. Lazo (Divino Niño); in Paraguay: M. Zegarra, H. Burga, J. C. Gines (Fundación Visión); in Guatemala: G. Pivaral, M. Yee (Visualiza); in Ecuador: F. Chiriboga (Fundación Oftalmológica Del Valle); In India: A. Haripriya (consultant), N. Srinivasan (coordinator), S. Preetha (coordinator) (Aravind Eye Hospital, Madurai), C. Shivkumar (consultant), D. Subha (coordinator) (Aravind Eye Hospital, Tirunelveli), T. Badrinath (consultant), P. Thilagavathy (coordinator), P. Jayanthi (coordinator) (Aravind Eye Hospital, Pondicherry), V. Prabhu (consultant), D. Vivek (coordinator) (Aravind Eye Hospital, Coimbatore), and D. Datta (consultant), P. Balasiva (coordinator) (Aravind Eye Hospital, Theni); and in Indonesia: A. Bani (Puskesmas Kopang, Puskesmas Tanjung).