An inventory of information on blindness and visual impairment in Canada

Background: Several health databases contain information on blindness and v isual impairment in Canada. Such databases may permit studies of the outcom es, predictors, economic costs and meta-analysis of ocular health problems and visual disability. In this paper we summarize the existing public healt h 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. Bot h literature searching and Internet searching were performed. The instituti ons were notified by email or telephone that information pertaining to visi on and blindness was desired. When necessary, we visited the institution to obtain the information. Results: Health administrative databases contain information on a wide cros s-section of diagnoses but are usually limited in detail and seldom provide longitudinal information. Health surveys have a limited amount of systemat ic information on vision-related questions and rely exclusively on self-rep orting. Registries exist on a wide range of visual topics. The Canadian Nat ional Institute for the Blind (CNIB) has the most comprehensive registry. Interpretation: This is the first attempt at summarizing all the public hea lth information on blindness and visual impairment in Canada. The present p opulation-based ocular information has numerous shortcomings. More comprehe nsive validation of large registries, such as that of the CNIB, is needed t o provide the foundation for a longitudinal ocular surveillance system. Suc h a system could guide research on risk factors and the effect of treatment , economic analyses, and public policy for ocular research and service allo cation.