A 2006 study found neurologists in the United States ordered more tests in theoretical clinical situations posed than their German counterparts; U.S. clinicians are more likely to fear litigation which may be due to the teaching of defensive strategies which are reported more often in U.S. teaching programs. Counting both direct and indirect costs, other studies estimate the total cost of malpractice between 5% and 10% of total U.S. medical costs.

Defensive medicine is the practice of diagnostic or therapeutic measures conducted primarily not to ensure the health of the patient, but as a safeguard against possible malpractice liability. Fear of litigation has been cited as the driving force behind defensive medicine. Defensive medicine is especially common in the United States of America, with rates as high as 79% to 93% , particularly in emergency medicine, obstetrics, and other high-risk specialties.

Defensive medicine takes two main forms: assurance behavior and avoidance behavior. Assurance behavior involves the charging of additional, unnecessary services in order to a) reduce adverse outcomes, b) deter patients from filing medical malpractice claims, or c) provide documented evidence that the practitioner is practicing according to the standard of care, so that if, in the future, legal action is initiated, liability can be pre-empted. Avoidance behavior occurs when providers refuse to participate in high risk procedures or circumstances.