Cost-sharing is regarded as an important tool to reduce moral hazard in health insurance. Contrary to standard prediction, however, such requirements are found to decrease utilization both of efficient and of inefficient care. I employ a simple model that incorporates two possible explanations -...

One of the main features of health insurance is moral hazard, as defined by Pauly (1968); people face incentives for excess utilization of medical care since they do not pay the full marginal cost for provision. To mitigate the moral hazard problem, a coinsurance can be included in the insurance...