Assessing Near Vision in the Rapid Assessment of Avoidable Blindness Survey Methodology: Results of Validation and Feasibility Studies in India and Togo

Introduction Half a billion people worldwide have near vision impairment from unaddressed presbyopia. To address this, the 2021 World Health Assembly endorsed a global target for increasing effective refractive error coverage (eREC) for near vision. However, there is a global population data gap on near vision. This study tested the validity and feasibility of including a Peek Vision smartphone-based near vision screening test in the Rapid Assessment of Avoidable Blindness (RAAB) survey to allow more epidemiological data to be collected on this important global health issue. Methods The study was done across four RAABs, two in India and two in Togo. In the first, the sensitivity and specificity of the Peek test was assessed to detect near vision impairment (cannot see N6 at 40 cm, binocularly) when compared to a printed near chart. Then, the feasibility was assessed with a review of teams’ ability to still complete one cluster per day with the new content in the protocol. The RAAB Steering Group reviewed the findings to determine whether the new near vision content should be included in all RAABs. Results The Peek near vision test had a sensitivity of 85.3% (95% CI: 80.3–89.4%) and a specificity of 88.2% (95% CI: 83.0–92.2%). This was considered sufficient to proceed with the feasibility assessment, and no implementation concerns were found in any survey. The RAAB Steering Group consultation recommended minor modifications to questions on spectacle ownership, and these questions were restricted to only those participants with a need for near vision correction. Conclusion The validity and feasibility of measuring near vision in RAAB surveys was confirmed. This new test will give eye care providers important information on the need for presbyopic correction in their population and start to build up the global evidence base for near eREC.