Progress in cancer screening over a decade

Abstract

Background: Screening to detect cancer early, an increasingly important cancer control activity, cannot be effective unless it is widely used.

Methods: Use of Pap smears, mammography, fecal occult blood tests (FOBTs), sigmoidoscopy, and digital rectal examination (DRE) was evaluated in the 1987, 1992, and 1998 National Health Interview Surveys. Levels and trends in screening use were examined by sex, age, and racial/ethnic group. The effects of income, educational level, and health care coverage were examined within age groups. Logistic regression analyses of 1998 data were used to develop a parsimonious, policy-relevant model.

Results: Use of all screening modalities increased over the period examined; for mammography and DRE, the increase was more rapid in the first half of the decade; for the Pap test and sigmoidoscopy, the increase was more rapid in the second half of the decade. Levels of colorectal cancer screening (both sigmoidoscopy and FOBTs) in 1998 were less than the level that prevailed a decade earlier for mammography. Patterns of change for all screening modalities differed between age, sex, and racial/ethnic groups, but prevalence of use during the study, within recommended time intervals, was consistently lower among groups with lower income and less education. Logistic regression analyses indicated that insurance coverage and, to a greater extent, usual source of care had strong independent associations with screening usage when age, sex, racial/ethnic group, and educational level were taken into account.

Conclusions: While cancer screening is generally increasing in the United States, usage is relatively low for colorectal cancer screening and among groups that lack health insurance or a usual source of care.