SUMMARY
For most doctors, obtaining medical malpractice insurance coverage each year represents a significant expense. During the past three decades, researchers have developed several competing theories to explain changes in the cost of obtaining medical malpractice insurance in the United States. This article focuses on the relationship, on a nationwide basis, between medical malpractice awards, the presence of tort reform, investment returns by insurers, and the impact of each upon the cost of obtaining medical malpractice insurance. The results of a multivariate equation are then used to analyze the relative impacts of these competing theories.