Mammography use among women as a function of age and patient involvement in decision-making

To assess the extent to which self-reported patient involvement in decision-making for initiation of mammography differs with age.

Data from the 1992 National Health Interview Survey (NHIS) Cancer Control Supplement were evaluated. Prevalences were weighted and variances were adjusted using SUDAAN software to account for the complex, multistage sampling probability design of the NHIS. Logistic regression was used to evaluate the relative likelihood of self-reported involvement in the decision to have a mammogram within the preceding year as a function of age and other covariates.

Mammography use was assessed among 3,863 NHIS female respondents 40 years of age or older. The analysis of decision-making was restricted to the subgroup of 1,064 women who reported a screening mammogram within the preceding year and who provided information on the other relevant variables.

The probability of reported mammography use within the preceding year declines among older groups of interviewees. Among women with a mammogram in the preceding year, the weighted percentage of women reporting active involvement in the decision (patient decision or decided jointly with a physician) declines from 51% among women 40 to 45 years of age to 19% among those aged 75 years or older. The adjusted odds ratio comparing the likelihood of participating in the decision to have a mammogram for the oldest women, compared with the youngest, was 0.31 (95% confidence interval 0.15 to 0.61).

Older women are substantially less likely than younger women to report active involvement in the mammography decision-making process. Increased use of screening mammography among older women will require greater promotion by physicians. Other interventions, such as directed educational efforts, may also be needed to increase mammography demand among older women.