Monitoring visual status: Why patients do or do not comply with practice guidelines

Objective. To determine factors affecting compliance with guidelines for annual eye examinations for persons diagnosed with diabetes mellitus (DM) or age-related macular degeneration (ARMD). Data Sources/Study Setting. Nationally representative, longitudinal sample of individuals 65+ drawn from the National Long-Term Care Survey (NLTCS) with linked Medicare claims records from 1991 to 1999. Study Design. Medicare beneficiaries were followed from 1991 to 1999, unless mortality intervened. All claims data were analyzed for presence of ICD-9 codes indicating diagnosis of DM or ARMD and the performance of eye exams. The dependent variable was a binary indicator for whether a person had an eye exam or not during a 15-month period. Independent variables for demographics, living conditions, supplemental insurance, income, and other factors affecting the marginal cost and benefit of an eye exam were assessed to determine reasons for noncompliance. Data Collection/Extraction Methods. Panel data were created from claims files, 1991-1999, merged with data from the NLTCS. Principal Findings. The probability of having an exam reflected perceived benefits, which vary by patient characteristics (e.g., education, no dementia), and factors associated with the ease of visit. African Americans were much less likely to be examined than were whites. Conclusions. Having an exam reflects multiple factors. However, much of the variation in the probability of an exam remained unexplained as were reasons for the racial differences in use.