Do tort reforms impact the incidence of birth by cesarean section? A reassessment.

Investigations into the existence and impact of defensive medicine in obstetrics have produced mixed and often conflicting implications. The most widely-cited and accepted results in this literature find that less severe malpractice environments cause an increase in the use of cesarean section. This has been interpreted as "offensive medicine"; taking advantage of lenient malpractice environments by providing unnecessary services in order to raise revenue. In this article we show that an assumption concerning births with an unknown method of delivery, which is not explicitly stated in the literature, is pivotal in obtaining these results. Using data on tort reforms and birth outcomes from 1989 to 2001 in 24 US states, we show that for the 98.4% of births with a confirmed method of delivery, the estimated effects of tort reform on C-section rates are insignificant. Therefore, without this assumption, there is little evidence to support an interpretation of offensive medicine.