When Guidelines Conflict: A Case Study of Mammography Screening Initiation in the 1990s

Cancer screening guidelines communicate important information to patients and physicians regarding the costs and benefits of screening. Currently, guideline recommendations from major organizations conflict regarding the age of mammography screening initiation. To understand current and future U.S. mammography screening patterns we study age-mammography patterns from the 1990s, another period of conflicting guideline recommendations.

We examine mammography use rates by single year of age to understand compliance with guideline-recommended initiation ages in the 1990s. Mammography test use data was taken primarily from the 1991 to 2001 Behavioral Risk Factor Surveillance System. The analytic sample included all women 35 to 54 years of age.

We found a discrete 8.7-percentage point increase in mammography use precisely at age 40 and a much smaller 1.6-percentage point increase in mammography use at age 50. These findings varied by insurance status, with the insured experiencing a large, discrete increase primarily at age 40 and the uninsured experiencing notable discrete increases at ages 40 and 50.

Physicians and patients converged primarily on the age 40 mammography screening threshold during the 1990s. Prices, along with guidelines, were key determinants of the age of screening initiation, with the insured responding to age 40 coverage and cost-sharing reductions and the uninsured affected by guidelines and public funding tied to the age 50 threshold. The policy factors underlying these results, recent ACA coverage increases, and ACA cost-sharing requirements imply that a substantial number of women will continue to receive mammography screening in their 40s.