Screening mammography referral rates for women ages 50 to 69 years by recently-licensed family physicians: physician and practice environment correlates

Background: Physician mammography referral remains below optimal levels despite a long-standing recommendation that all women ages 50 to 69 years receive screening mammography every 1 to 2 years. The purpose of this study was to determine physician and practice environment predictors of family physicians' screening mammography referral rates to women ages 50-69 years.

Method: A cohort of 498 recently-licensed family physicians was followed for 18-months of incipient medical practice. The referral rate was the percentage of new clinically eligible women patients seen in a primary care context who had a screening mammogram ordered by the study physician. Mammograms and independent variables were identified from physician claims to a Canadian universal health insurance agency. The effects of factors in a conceptual framework were assessed using multivariable linear regression.

Results: Correlates of higher mammography referral rates were female gender, better general prevention knowledge, the combination of comprehensive inquiry and continuity care, lower patient volume, and lower shared primary care (multivariable model R(2) = 0.47). Factors belonging to practice environment explained more of the observed variance than did physician characteristics.

Conclusions: Mammography referral varies enormously and almost half of the variance is explained by physician characteristics and practice preferences. Higher mammography referral is observed in practices with more comprehensive and continuity care.