Health Insurance Reform and HMO Penetration in the Small Group Market
NBER Working Paper No. 11446
We use data from several national employer surveys conducted between the late 1980s and the mid-1990s to investigate the effect of state-level underwriting reforms on HMO penetration in the small-group health insurance market. We identify reform effects by exploiting cross-state variation in the timing and content of reform legislation and by using mid-sized and large employers, which were not affected by the legislation, as within-state control groups. While it is difficult to disentangle the effect of state reforms from other factors affecting HMO penetration in the small group markets, the results suggest a positive relationship between insurance market regulations and HMO penetration.
Published: Buchmueller, Thomas C. and Su Liu. “Health Insurance Reform and HMO Penetration in the Small Group Market.” Inquiry 42, 4 (Winter 2005/2006).