Background: ACA removed cost sharing for preventive services including cancer screenings such as mammography and pap smear. In 2015, 65.3% of women >=40 years had a mammogram within previous two years, while 70.4% of women >=18 years had a pap test within three years.

OBJECTIVES: identify the impact of ACA on mammography and pap smear utilization rates by predicting the rates with and without ACA so that differential effects of ACA on screening rates by demographics, socioeconomics, and health status can be identified.

METHODS:

Data source: The Medical Expenditure Panel Survey (MEPS) data for the years 2008 (pre- ACA) and 2015 (post- ACA). Mammography cohort included women aged >= 40 and pap smear cohort included women aged >= 21. There were 14,047 women in mammography cohort and 22,342 women in pap smear cohort.

Measures: main outcomes are the receipt of mammography and pap smear; the covariates are income, insurance, age, race, education, marital status, region, and comorbidity.

Statistical analysis: Multivariate logistic model was run to explain the likelihood of mammography and pap smear screenings pre-ACA. The estimated model was used to predict utilization of screenings in post-ACA years in absence of ACA. Differences between predicted probabilities and actual use reflect ACA-effects.

RESULTS: Mammography coverage would have been 71% in 2015 without ACA but the actual coverage was 70%. Some population subgroups showed statistically significantly higher mammography use than predicted such as middle-income group, aged 51-64, separated, and low-educated. Pap smear coverage would have been 79% in 2015 without ACA but the actual coverage was 76%.

CONCLUSIONS: We observed no impact of removing cost-sharing under the ACA on mammography and pap smears coverage rate. Financial barrier may not be the most important factor affecting utilization of screenings.