Article
Quarterly Journal of Economics

Behavioral Hazard in Health Insurance

By: Katherine Baicker, Sendhil Mullainathan and Joshua Schwartzstein

Format:Print

Abstract

A fundamental implication of standard moral hazard models is overuse of low-value medical care because copays are lower than costs. In these models, the demand curve alone can be used to make welfare statements, a fact relied on by much empirical work. There is ample evidence, though, that people misuse care for a different reason: mistakes or "behavioral hazard." Much high-value care is underused even when patient costs are low, and some useless care is bought even when patients face the full cost. In the presence of behavioral hazard, welfare calculations using only the demand curve can be off by orders of magnitude or even be the wrong sign. We derive optimal copay formulas that incorporate both moral and behavioral hazard, providing a theoretical foundation for value-based insurance design and a way to interpret behavioral "nudges." Once behavioral hazard is taken into account, health insurance can do more than just provide financial protection—it can also improve health care efficiency.

Keywords

Insurance; Consumer Behavior; Health Care and Treatment; Insurance Industry

Citation

Baicker, Katherine, Sendhil Mullainathan, and Joshua Schwartzstein. "Behavioral Hazard in Health Insurance." Quarterly Journal of Economics 130, no. 4 (November 2015): 1623–1667. (Online Appendix.)