Subgroup-specific effects of questionnaire wording on population-based estimates of mammography prevalence

Abstract

Objectives. This study investigated whether an apparent downturn in prevalence rates of mammography use reported in the 1992 Behavioral Risk Factor Surveillance System (BRFSS) questionnaire resulted from a change in questionnaire wording. Methods. In a pretest - Posttest design (1990-1991 vs 1992), piecewise linear regression analyses were based on monthly prevalence estimates of mammography use among female BRFSS respondents 40 years or older Results. Self-reported mammography use was lower by 3.5 percentage points (95% confidence interval [CI] = 1.5, 5.5) overall - And lower by 13.6 percentage points (95% CI = 2.6, 24.6) among Black women with less than a high school education - When predicted from 1992 data than when predicted from 1990-1991 data. Conclusions. A change in questionnaire wording in the BRFSS caused demographic-specific effects in population-based estimates of mammography use.