Changes in Marketplace competition and television advertising by insurers.

Objectives: The Trump administration ended television advertising for the Health Insurance Marketplace prior to the 2018 open enrollment period, leaving insurers as the predominant source of health insurance advertising. Prior research findings are mixed on the effectiveness of private advertising on Marketplace enrollment, but no work to date has examined how competitive changes in health insurance markets are related to marketing patterns. This study provides the first evidence on how insurers are altering their marketing in response to changes in competition.

Study Design: This study links data capturing Marketplace participation (CMS Qualified Health Plan Landscape files) by county and health insurance advertising (Kantar Media/Campaign Media Analysis Group) by media market for the 2014 through 2018 open enrollment periods.

Methods: We used population-weighted county fixed effects models to estimate the relationship between year-over-year changes in Marketplace competition and changes in (1) total private advertising and (2) advertising per insurer.

Results: Going from multiple insurers to a single insurer resulted in 465 fewer private ads aired within a county during open enrollment (P < .01), a 17% to 38% reduction. Losing monopoly status is associated with a drop in advertising of 452 airings per insurer (P < .01), and becoming a monopolist is associated with 293 more airings per insurer (P < .01).

Conclusions: Insurers are not replacing the decline in government-sponsored advertising. We find that insurers behave as if they are responding to strategic incentives, advertising more when they become a monopolist but not filling the hole left by their former competitor, which has implications for the volume of messages seen by consumers.