This paper studies risk selection between public and private health insurance when some individuals can purchase private insurance by opting out of otherwise mandatory public insurance. Using a theoretical model, I show that public insurance is adversely selected when insurers and insureds are symmetrically informed about health-related risks, and that selection can be of any type (advantageous or adverse) when insureds have private information about health risks. Drawing on data from the German Socio-Economic Panel, I find that: (1) public insurance is adversely selected under the German public health insurance with opt-out scheme, (2) individuals adversely select public insurance based on self-assessed health and advantageously select public insurance based on risk aversion, and (3) there is evidence of asymmetric information.

This paper investigates whether doctors prescribe antibiotics to protect themselves against potential malpractice claims. Using data from the National Ambulatory Medical Care Survey on more than half a million outpatient visits between 1993 and 2011, I find that doctors are 6% less likely to prescribe antibiotics after the introduction of a cap on noneconomic damages. Over 140 million discharge records from the Nationwide Inpatient Sample do not reveal a corresponding change in hospital stays for conditions that can potentially be avoided through antibiotic use in the outpatient setting. These findings, as well as a stylized model of antibiotic prescribing under the threat of malpractice, suggest that liability-reducing tort reforms can decrease the amount of antibiotics that are inappropriately prescribed for defensive reasons.

This paper studies whether doctors prescribe antibiotics to protect themselves against potential malpractice claims. Using data from the National Ambulatory Medical Care Survey on a representative sample of doctor visits from 1993 to 2011, I find that doctors are significantly less likely to prescribe antibiotics following tort reforms that reduce malpractice pressure. The changing prescribing patterns appear to have no adverse effects on patient health outcomes over the same time period. Almost 100 million hospital records from the Nationwide Inpatient Sample reveal little to no effects of tort reforms on hospital stays involving conditions that can potentially be avoided through the timely use of antibiotics. Taken together, these findings suggest that malpractice pressure induces doctors to prescribe antibiotics that are medically unnecessary, thereby contributing to the rise in antibiotic resistance.