Universal health insurance and equity in primary care and specialist office visits: a population-based study.

PURPOSE: Universal coverage of physician services should serve to reduce socioeconomic disparities in care, but the degree to which a reduction occurs is unclear. We examined equity in use of physician services in Ontario, Canada, after controlling for health status using both self-reported and diagnosis-based measures.
METHODS: Ontario respondents to the 2000-2001 Canadian Community Health Survey (CCHS) were linked with physician claim files in 2002-2003 and 2003-2004. Educational attainment and income were based on self-report. The CCHS was used for self-reported health status and Johns Hopkins Adjusted Clinical Groups was used for diagnosis-based health status.
RESULTS: After adjustment, higher education was not associated with at least 1 primary care visit (odds ratio [OR] = 1.05; 95% confidence interval [CI], 0.87-1.24), but it was inversely associated with frequent visits (OR = 0.77; 95% CI, 0.65-0.88). Higher education was directly associated with at least 1 specialist visit (OR = 1.20; 95% CI, 1.07-1.34), with frequent specialist visits (OR = 1.21; 95% CI, 1.03-1.39), and with bypassing primary care to reach specialists (OR = 1.23, 95% CI 1.02-1.44). The largest inequities by education were found for dermatology and ophthalmology. Income was not independently associated with inequities in physician contact or frequency of visits.
CONCLUSIONS: After adjusting for health status, we found equity in contact with primary care for educational attainment but inequity in specialist contact, frequent visits, and bypassing primary care. In this setting, universal health insurance appears to be successful in achieving income equity in physician visits. This strategy alone does not eliminate education-related gradients in specialist care.