Impact of primary care patient visits on racial and ethnic disparities in preventive care in the United States.

BACKGROUND: The causes of racial and ethnic disparities in preventive care are not fully understood. We examined the hypothesis that fewer primary care visits by minority patients contribute to these disparities.
METHODS: We analyzed claims for Medicare beneficiaries 65 and older who participated in the Medicare Current Beneficiary Survey, 1998 to 2002. Five preventive services were included: colorectal cancer testing, influenza vaccination, lipid screening, mammography, and Papanicolaou smear screening. In separate multivariate analyses, we examined the effect of minority status (self-report of African American race or Hispanic ethnicity) on having a claim in the past 12 months for each preventive service after successive control for number of primary care visits and other patient characteristics.
RESULTS: The final sample included 15,962 subjects. In age-adjusted analyses, minorities had statistically lower rates of claims for each of the 5 procedures. After controlling for number of primary care visits, the effect of minority status was slightly attenuated but remained statistically significant for receipt of each procedure. After adding low income, low educational level and supplementary insurance, health status, and year, minority status was significantly associated only with colorectal cancer screening (odds ratio [OR] 0.79; 95% confidence interval [CI] 0.67 to 0.94) and influenza vaccinations (OR 0.56; 95% CI 0.49 to 0.64).
CONCLUSIONS: The frequency of primary care visits seems to contribute minimally to racial and ethnic disparities in preventive services. Other patient characteristics, particularly those associated with poverty, explain much of these disparities.