Background: Substantial differences exist in estimates of the proportion of elderly women who undergo screening mammography and the impact of race and ethnicity on mammography usage.
Methods: A representative 5% sample of elderly women living in 11 Surveillance, Epidemiology, and End Results areas from 1991 to 2001 was constructed using Medicare data. Biennial rates of screening mammography (at least one mammogram within each 2-year period) were calculated for overlapping 2-year periods, adjusting to a 2000-2001 age and race distribution. Multivariate repeated-measures logistic regression was used to examine predictors of screening usage.
Results: The sample included 146,669 women. Between 1991 and 2001 the age- and race-adjusted proportion of women aged 65 years and older who underwent at least biennial screening mammography increased from 35.8% to 47.9%. Mammography screening increased for all racial and ethnic groups, but remained significantly higher for non-Hispanic white women as compared with all other groups. The biennial screening rate in 2000-2001 was 50.6% for non-Hispanic white, 40.5% for African-American, 34.7% for Asian-American, 36.3% for Hispanic, and 12.5% for Native-American women. After controlling for age, site, physician access, comorbidities, education, and income, African Americans (odds ratio [OR] = 0.80, 95% confidence interval [CI] = 0.78-0.83), Asian Americans (OR=0.53, CI = 0.51-0.55), Hispanics (OR = 0.70, CI = 0.67-0.74), and Native Americans (OR=0.37, CI=0.29-0.46) were still all less likely than non-Hispanic white women to undergo screening.
Conclusions: Elderly women undergo significantly less mammography screening than is suggested by self-reported surveys. All groups of non-white women undergo less screening than do white women. The magnitude of the difference in screening rates comparing Asian-American and Hispanic women with white women is especially large; however, other studies have questioned the sensitivity of Medicare data for identifying people of Asian and Hispanic ethnicity. For African-American women, the magnitude of the gap is smaller, but it is of concern that the gap in screening as compared with white women has grown over time.