Factors associated with adherence to recommendations for screening mammography among American Indian women in Colorado.

Objective: To compare adherence to screening mammography recommendations of American Indian and non-Hispanic White women in the Denver, Colorado, area.

Design/setting/participants: This study retrospectively examined adherence patterns in 229 American Indian and 60,197 non-Hispanic White women > or = 40 years and older, with at least one screening mammogram in the Colorado Mammography Project (CMAP), from January 1, 1999, to December 31, 2003. The CMAP was a prospective study of women receiving mammograms at participating clinics around Denver.

Main Outcome Measures: Using logistic mixed models, we defined two dependent variables as annual and biennial adherence from the intervals between screening mammograms for each woman.

Results: Biennial adherence was substantially higher than annual adherence for both American Indian and non-Hispanic White women in our analyses. American Indian women were less likely than non-Hispanic White women to adhere to biennial recommendations in multivariate models controlling for age, family history of breast cancer, and economic status (zip code): odds ratio (OR) .4 and 95% confidence interval (CI) .2-.6. The association between American Indian race/ethnicity and annual adherence was similar, although not as strong (OR .5, 95% CI .3-.8).

Conclusions: American Indian women in the CMAP cohort were less likely than non-Hispanic White women to adhere to recommendations for screening mammography, both annually and biennially. Additional research is needed to explore the effect of biennial screening and other barriers among American Indian women.