Abstract
OBJECTIVE: To establish consensus definitions for non-visually impairing eye conditions (NVICs) and their methods of assessments to provide standards for use in population-based eye surveys. DESIGN: A literature review of NVICs in sub-Saharan Africa, a questionnaire of inquiry based on the literature review developed by an expert panel and a modified Delphi exercise with three iterative rounds with eye health experts. SETTING: Eye health academia and community eye health in Nigeria. PARTICIPANTS: Nigerian ophthalmologists, including subspecialists experienced in population-based eye health surveys. MAIN OUTCOME MEASURES: Definitions and statements where at least 70% of the respondents agreed or strongly agreed. RESULTS: Forty-two ophthalmologists practising in Nigeria with experience in conducting population-based eye health surveys were invited to take part in the Delphi exercise. There were three rounds with response rates of 39/42 (92.9%) in round 1, (94.9%) in round 2 and 100% in round 3. Consensus for NVICs to be included in population-based eye surveys, their definitions and methods for assessment was reached by the third round. CONCLUSIONS: We propose case definitions for NVICs to be assessed in population-based eye surveys through a modified Delphi approach with an expert panel of ophthalmologists from across Nigeria. These case definitions will allow for standardisation of NVICs in population-based eye surveys to assess the prevalence and magnitude of the different types of NVICs for planning purposes. Further studies are needed to validate these case definitions and inform their evolution.