Mammography utilization among california women age 40-49 in a managed care environment.

Objective: To examine the utilization of screening mammography and the relationship between risk factors and mammography use in women age 40-49 in a managed care environment.
Design: Retrospective observational study based on a mailed survey.
Setting: A large HMO in California.
Patients/participants: The study population included respondents age 40-49 who completed a breast health assessment questionnaire mailed to all women age 34-49 and enrolled in a California HMO in early 1997.
Main Results: About 67.6% of the 20,391 women age 40-49 had at least one mammogram during 1995 and 1996. Logistic regression revealed that women age 40-44 were less likely (odds ratio: 0.83-0.90) than women age 45-49 to obtain mammography. Family history of breast cancer (odds ratio: 1.12-1.16), breast biopsy (odds ratio: 1.14-1.18), and a mammogram in the previous three years (odds ratio: 1.15-1.18) were associated with an increased likelihood of taking a mammogram. However, monthly breast self-exams (odds ratio: 0.996-1.04), having a child at or after age 30 (odds ratio: 0.97-1.02), and having menarche at age 12 or younger (odds ratio: 0.96-1.01) had no significant effect on the screening mammography rates.
Conclusion: A relatively higher percentage of younger HMO members receive screening mammography than that of general population. However, some higher-risk groups, especially women whose first pregnancies were late in life, do not show a higher rate of using mammography.