Interventions to Increase Affordable Care Act Marketplace Enrollment: A Systematic Review and Meta-Analysis

Over 10 million uninsured individuals are eligible for subsidized health insurance coverage through the Affordable Care Act (ACA) marketplaces, and millions more were projected to become eligible with the end of the federal COVID-19 Public Health Emergency in 2023. Individual studies on behaviorally informed interventions designed to encourage enrollment suggest that some are more effective than others. This study summarizes evidence on the efficacy of these interventions and suggests which administrative burdens might be most relevant for potential enrollees. Published and unpublished studies were identified through a systematic review of studies assessing the impact of behaviorally informed interventions on ACA marketplace enrollment from 2014 to 2022. Thirty-four studies comprising over 18 million participants were included (32 randomized controlled trials and 2 quasiexperimental studies). At the time of data extraction, 8 were published. Twenty-seven of the studies qualified for inclusion in a meta-analysis, which found that the average rate of enrollment was about 1 percentage point higher for those who received an intervention (0.009, P < 0.001), a 24% increase relative to control households; for every 1000 people who receive an intervention, that would correspond to about 9 additional enrollees. When stratifying by intervention intensity, support-based interventions increased enrollment by 2 percentage points (0.020, P = 0.004), while information-based interventions increased enrollment by 0.6 percentage points (0.006, P < 0.001). The meta-analysis found that behaviorally informed interventions can increase ACA marketplace enrollment. Interventions aimed at alleviating compliance costs by providing enrollment support were about three times as effective as information alone.