An inventory of information on blindness and visual impairment in Canada

Background: Several health databases contain information on blindness and visual impairment in Canada. Such databases may permit studies of the outcomes, predictors, economic costs and meta-analysis of ocular health problems and visual disability. In this paper we summarize the existing public health information on blindness and visual impairment in Canada. Methods: A systematic search was performed to find the information in three areas: health administrative databases, health surveys and registries. Both literature searching and Internet searching were performed. The institutions were notified by email or telephone that information pertaining to vision and blindness was desired. When necessary, we visited the institution to obtain the information. Results: Health administrative databases contain information on a wide cross-section of diagnoses but are usually limited in detail and seldom provide longitudinal information. Health surveys have a limited amount of systematic information on vision-related questions and rely exclusively on self-reporting. Registries exist on a wide range of visual topics. The Canadian National Institute for the Blind (CNIB) has the most comprehensive registry. Interpretation: This is the first attempt at summarizing all the public health information on blindness and visual impairment in Canada. The present population-based ocular information has numerous shortcomings. More comprehensive validation of large registries, such as that of the CNIB, is needed to provide the foundation for a longitudinal ocular surveillance system. Such a system could guide research on risk factors and the effect of treatment, economic analyses, and public policy for ocular research and service allocation.