Estimating Prevalence of Abortion Using List Experiments: Findings from a Survey of Women in Delaware and Maryland

Background: Widespread underreporting of abortion persists in survey data. The list experiment, a measurement tool designed to elicit truthful responses to sensitive questions, may alleviate underreporting. Methods: Using The Statewide Survey of Women of Reproductive Age in Delaware and Maryland (n = 2,747), we estimate the prevalence of abortion in Maryland and Delaware using a double list experiment. Results: We find 21% (95% confidence interval [CI]: 16.8%-25.3%) of respondents aged 18 to 44 ever had an abortion and we identify disparities in abortion prevalence by age, race, education, income, marital status, and insurance status. Respondents who were Black (37.0%; 95% CI: 27.1%-46.8%), had less than a college degree (24.8%; 95% CI: 18.3%-31.3%), were in a cohabiting relationship (39.0%; 95% CI: 29.1%-48.9%), were living in households with incomes less than $50,000 (28.6%; 95% CI: 19.7%-37.5%), and were currently covered by Medicaid (42.8%; 95% CI: 27.6%-58.0%) were more likely than their counterparts to have ever had an abortion. Conclusions: List experiments yield estimates of abortion substantially higher than those obtained from direct questions. Findings demonstrate external validity through consistency with estimates from administrative data sources and gold standard abortion provider survey data. (C) 2021 Jacobs Institute of Women's Health, George Washington University. Published by Elsevier Inc. All rights reserved.