Effect of Vision Centers on Access to Eye Care and Eye Health Outcomes

Not Applicable

Not yet recruiting

• Conditions: Cataract Surgery; Eye Care; Glasses; Primary Eye Care; Vision Center; Eyecare Visits

• Registration Number: NCT07227714
• Lead Sponsor: University of California, San Francisco

Brief Summary

The goal of this clinical trial is to evaluate the effect of vision centers on access to eye care and eye health outcomes in South Asia. The main questions it aims to answer are:

1. Do vision centers increase visits to eyecare centers?

2. Do vision centers increase spectacle ownership and wearing?

3. Do vision centers improve visual acuity of the population?

Researchers will compare outcomes in communities randomized to have a vision center is established with communities randomized to delay establishment of a vision center. Outcomes will be assessed through population-based surveys at baseline and after two years as well as through hospital records collected throughout the study period.

Detailed Description

The vast majority of visual impairment and blindness is preventable or treatable with existing interventions. Nearly all of this burden is faced by those living in low- and middle-income countries. Access to eye care is a key challenge in these settings, particularly in rural and remote areas.

Vision centers (VCs) have been developed to increase access to primary eye care in such underserved settings. VCs typically involve establishment of a fixed center staffed by a mid-level ophthalmic technician who offers refraction, spectacles, diagnosis and treatment of basic eye conditions, and referrals for more complex care. VCs have become a common approach to increase access to care in many low- and middle-income country settings, yet little rigorous evidence exists on their impact on eye health in the communities they serve. A recent literature review was unable to identify randomized controlled trials on the impact of vision centers on eye health outcomes in real world settings. While the observational research that exists suggests VCs improve eye health in the communities they serve, the existing evidence is prone to bias.

We propose a cluster-randomized trial to evaluate the effect of VCs on access to eye care and eye health outcomes in South Asia. The trial will leverage VCs planned by the Seva Foundation and partners Bangladesh, India, and Nepal and will monitor outcomes via population-based surveys and hospital network records over 2 years. We expect to provide rigorous evidence on VC impact in real-world settings that can be used to influence programmatic decision making and policy.

Study Timeline

• Status Verified: 2025-11
• Study First Submitted: 2025-11-10
• Study First Submitted QC: 2025-11-10
• Last Update Submitted: 2025-11-10
• Study First Posted: 2025-11-13
• Last Update Posted: 2025-11-13
• Study Start: 2026-03-01
• Primary Completion: 2028-06-01
• Study Completion: 2028-09-01

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 40000

Inclusion Criteria

• The catchment area of the proposed VC site is predominantly rural.
• The proposed VC site is located within 20-100 km of the base hospital.
• There are no major primary eye care services within 10 km of the proposed site.
• Care at sites randomized to establish VCs immediately is accessible to anyone.

Exclusion Criteria

• Sites located in non-rural or urban catchment areas.
• Sites outside the 20-100 km distance range from the base hospital.
• Sites with existing major primary eye care services within a 10 km radius.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Primary Outcome Measures

Name	Time	Method
Prevalence of eyecare visits	1 year	The primary outcome is the prevalence of eyecare visits completed in the past one year, defined for each cluster as the number of individuals having completed at least one visit in the past year divided by the total number of individuals surveyed.

Secondary Outcome Measures

Name	Time	Method
Total number of visits to any eyecare provider	1 year	Total number of visits to any eyecare provider within the past 12 months as reported during the survey (overall and among those with visual impairment).
Prevalence of current spectacle ownership	2 years.	Prevalence of current spectacle ownership assessed during the population-based survey among all age groups.
Effective refractive error coverage	2 years	Defined as the proportion of survey participants with met need for refractive error correction with good quality vision of 6/12 or better in the better seeing eye divided by the total number of people in need (met need + undermet need + unmet need).
Prevalence of spectacle wearing	2 years	Prevalence of spectacle wearing as assessed during the survey among all age groups.
Mean presenting and pinhole visual acuity	2 years	Mean presenting and pinhole visual acuity (logMAR) as assessed during the survey among adults 50 years and older, among children younger than 18 years, and among all ages.
Prevalence of visual impairment	2 years	Visual impairment is defined as presenting visual acuity worse than logMAR 0.54 in the better-seeing eye as assessed during the population-based survey, for adults aged 50 years and older, children younger than 18 years, and all ages.
Prevalence of blindness	2 years	Blindness is defined as presenting visual acuity worse than logMAR 1.30 in the better-seeing eye as assessed during the population-based survey, for adults aged 50 years and older, children younger than 18 years, and all ages.
Number of eye surgeries	2 years	Number of eye surgeries as reported by participants during the survey among adults 50 years and older.
Prevalence of other ocular diagnoses and treatment/procedures	2 years	Prevalence of other ocular diagnoses and treatment/procedures assessed during the population-based survey among all age groups.
Prevalence of employment	2 years	Prevalence of employment as assessed during the population-based survey among adults 18 years and older.
Mean annual household income	2 years	Mean annual household income as assessed during the population-based survey, converted to a common currency (USD) and adjusted for purchasing power parity (international dollars).
Prevalence of individuals with caregiving responsibilities for visually impaired household members	2 years	Prevalence of individuals with caregiving responsibilities for visually impaired household members assessed during the population-based survey.
Total number of network visits	2 years	Captured from passive surveillance
Cause-specific number of network visits	2 years	Number of network visits for specific causes including cataract, refractive error, diabetic retinopathy, glaucoma, and age-related macular degeneration, captured by passive surveillance of hospital data.
Number of cataract surgeries performed	2 years	Captured from passive surveillance
Cost of vision center implementation	2 years	Program costs of vision center implementation will be measured, with cost categories including personnel, equipment, supplies, training, transportation, and infrastructure.
Cost effectiveness of vision center	2 years	The cost effectiveness will be calculated as the incremental cost per additional cataract surgery performed in the intervention arm. Incremental cost-effectiveness ratios (ICERs) will be calculated using program costs and cataract surgeries enumerated from the hospitals during the study time period.

Trial Locations

Locations (1)

University of California, San Francisco; 🇺🇸 San Francisco, California, United States