Village-Integrated Eye Worker Trial II

Study Overview
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Brief Summary
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The vast majority of blindness is avoidable. The World Health Organization (WHO) estimates that 80% of cases of visual impairment could be prevented or reversed with early diagnosis and treatment. The leading causes of visual impairment are cataract and refractive error, followed by glaucoma, age-related macular degeneration (AMD), and diabetic retinopathy (DR). Loss of vision from these conditions is not inevitable; however, identifying at-risk cases and linking cases with appropriate care remain significant challenges. To address the global burden of avoidable blindness, eye care systems must determine optimal strategies for identifying people with or at risk for visual impairment beyond opportunistic screening. Outreach programs can prevent blindness both by screening for asymptomatic disease like age-related macular degeneration (AMD), diabetic retinopathy (DR), and glaucoma and case detection of symptomatic disease like cataract and refractive error. Eye care systems have developed numerous community-based approaches to these identification methods, including screening using telemedicine and case detection via cataract camps or community health worker models, but no studies have been conducted on the comparative effectiveness or cost effectiveness of these various approaches. Technology promises to greatly improve access to sophisticated eye care. AMD, DR, and glaucoma can result in irreversible vision loss, and early diagnosis and effective treatment can prevent progression.Thus, community screening programs may prevent progression and improve the vision of a population.However, mass screening for eye disease is currently not recommended. Although self-evident that early detection can prevent blindness for an individual, no randomized controlled trial has been able to demonstrate that screening improves visual acuity at the community level. However, recent technological advances promise to dramatically change the equation by allowing non-medical personnel to use mobile,easy-to-use retinal imaging devices to diagnose screenable eye diseases such as AMD, DR, and glaucoma. Mobile technology could also transform the way clinics communicate with their patients, improving linkage to and retention in care. Optical coherence tomography (OCT) is an ideal test for community-based screening. OCT can be performed through an undilated pupil and is less subject to optical aberrations due to cataract than is fundus photography. OCT machines have pre-installed algorithms to screen for glaucoma, and major anatomical abnormalities can easily be detected even by novice technicians. The infrared image allows detection of referable diabetic retinopathy, and newer OCT angiography machines offer even more discrimination of early diabetic retinopathy. OCT machines are ever more portable, and could be feasibly used in community-based screening programs. The investigators propose a large cluster-randomized trial in Nepal to compare two community-based blindness prevention programs: (1) a state-of-the-art screening program employing OCT and intraocular pressure testing to screen for glaucoma, DR, and AMD followed by enhanced linkage-to-care to the local eye hospital, and (2) a screening program involving only visual acuity assessment. An initial door-to-door census will assess baseline visual acuity in both study arms. The investigators will compare visual acuity between the two arms through a second door-to-door census 4 years later (primary outcome). The investigators maximize their chances of finding an effect by conducting the study in Nepal, where the burden of undiagnosed eye diseases is high. If successful in Nepal, future studies could assess the generalizability of such a program to other settings, such as rural communities in the industrialized world.

Detailed Description
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The research will consist of a large cluster-randomized trial in Nepal in which all communities receive visual acuity screening during a baseline census, and then half subsequently receive screening with OCT and intraocular pressure testing with an iCare tonometer. Participants with abnormal results will be referred to the local eye hospital for examination and treatment. Repeat visual acuity assessment will be performed 4 years later. Those with incident visual impairment at the time of the final census, defined as visual acuity worse than Snellen 20/60 (Metric Snellen worse than 6/18; logMAR worse than 0.48), will receive a comprehensive eye exam to determine the cause of visual impairment. Specific Aim 1 - Visual Acuity: To determine whether an intensive screening program results in better visual acuity at 4 years than screening with visual acuity testing alone. The investigators hypothesize that individuals from clusters randomized to the intensive screening program will have better visual acuity compared to those receiving visual acuity testing alone. Specific Aim 2 - Eye Disease: To determine whether an intensive screening program reduces the incidence of visual impairment due to AMD, DR, or glaucoma. The investigators hypothesize that incident visual impairment due to AMD, DR, or glaucoma will be less common in clusters randomized to the intensive screening program.

Official Title
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Village-Integrated Eye Worker Trial II (VIEW II):A Cluster-randomized Trial of the Effectiveness of Community-based Ocular Disease Screening in Nepal

Conditions
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Age-related Macular Degeneration, Diabetic Retinopathy, Glaucoma

Intervention / Treatment
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* Other: Visual acuity (presenting and pinhole)
* Other: Optical coherence tomography (OCT)
* Other: Intraocular pressure
* Other: Active linkage to care


Participation Criteria
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Eligibility Criteria
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Community level Inclusion Criteria: Located in catchment area of Bharatpur Eye Hospital or Lumbini Eye Institute Accessible by non-4WD vehicle Urban or peri-urban Exclusion Criteria: - Local leaders unwilling to participate Person level Inclusion Criteria: 60 years and older Residing in the community during the time of the census Exclusion Criteria: - Unwilling to participate

Ages Eligible for Study
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Minimum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Screening
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Screening<br> | Other: Visual acuity (presenting and pinhole)<br>* Presenting and pinhole visual acuity will be assessed using the Peek Acuity mobile application. Participants meeting referral criteria will be referred to the nearest eye care center or eye hospital.<br>Other: Optical coherence tomography (OCT)<br>* OCT will be used to image the anterior segment, the macula, and the retinal nerve fiber layer. The images will be assessed for abnormalities and participants meeting referral criteria will be referred to the local eye hospital.<br>Other: Intraocular pressure<br>* Intraocular pressure will be measured using an iCare tonometer. Participants meeting referral criteria will be referred to the nearest eye care center or eye hospital.<br>Other: Active linkage to care<br>* Referred participants will be followed closely by study staff to ensure completion of follow-up visits.<br>|
| Active Comparator: Case detection<br> | Other: Visual acuity (presenting and pinhole)<br>* Presenting and pinhole visual acuity will be assessed using the Peek Acuity mobile application. Participants meeting referral criteria will be referred to the nearest eye care center or eye hospital.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pinhole visual acuity (logMAR) in people aged 60 years and older | Visual acuity will be assessed using the Peek Acuity mobile application during the final census. | 4 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of visual impairment due to AMD, DR, or glaucoma | Participants with incident visual impairment, defined as Snellen worse than 20/60 (Metric Snellen worse than 6/18; logMAR worse than 0.48), at the time of the final census will receive a comprehensive eye exam to determine the cause of visual impairment | 4 years | 
| Bilateral blindness in people aged 60 years and older, defined as pinhole visual acuity worse than Snellen 20/400 (Metric Snellen worse than 6/120; logMAR worse than 1.3) in the better-seeing eye | Visual acuity will be assessed using the Peek Acuity mobile application during the final census. | 4 years | 
| Presenting visual acuity (logMAR) in people aged 60 years and older | Visual acuity will be assessed using the Peek Acuity mobile application during the final census. | 4 years | 
| Cost-effectiveness of the screening intervention | Costs associated with the screening intervention will be actively recorded during the study period and number of cases of AMD, DR, and glaucoma diagnosed and visual acuity as assessed with Peek Acuity during the final census will be used to evaluate effectiveness. | 4 years |