Recent research has shown that diagnostic errors were the most common basis for successful medical malpractice claims from 1986 to 2010. A study of such claims in the National Practitioner Data Bank revealed that incorrect, missed or delayed diagnoses made up 29 percent of the nearly 350,000 successful malpractice claims filed during that period. The study was conducted by neurologists at Johns Hopkins University School of Medicine and appears in BMJ Quality & Safety.
The study simply reviewed successful medical malpractice claims over the given time period. It did not seek to answer the question of why diagnostic errors are as common as they are. One of the two leading authors of the study referred to the diagnostic process as "complicated" and suggested that uncertainty and time pressure were complicating factors in making an accurate diagnosis. He further pointed out that there is no public reporting requirement for "measuring diagnostic accuracy or error."
Diagnostic errors that resulted in successful medical malpractice claims involved fatal mistakes in 41 percent of cases. These errors led to an average payment of $389,000, with individual results varying widely depending on the circumstances of the case. The total payments in cases involving missed diagnoses, delayed diagnoses and incorrect diagnoses made up 35 percent of all money paid in medical malpractice claims.
Source: The Washington Post, "Diagnostic errors are leading cause of successful malpractice claims," by David Brown, 22 April 2013