Diagnostic Mistakes Are Top Cause of Malpractice Awards, Study Finds

Diagnostic errors -- not surgical, obstetrical or medication mistakes -- are the leading cause of successful malpractice claims, but little is being done to identify and correct such errors, according to a study published online by BMJ Quality & Safety, the Washington Post reports.

Johns Hopkins University researchers examined 25 years of malpractice data from the National Practitioner Data Bank, looking specifically at about 350,000 malpractice allegations from 1986 to 2010 that led to payouts.

The study found that diagnostic errors -- defined as missed, wrong or delayed diagnoses -- accounted for nearly 29% of all successful claims, followed by:

• Treatment inaccuracies (27%);
• Surgical mishaps (24%);
• Obstetrical problems (7%);
• Medication errors (5%); and
• Anesthesia complications (3%) (Brown, Washington Post, 4/22).

The study also found that 40% of diagnosis-related claims resulted in death. Meanwhile, diagnostic errors made up 35.2% of total payments, or $38.8 billion adjusted for inflation (Landro, Wall Street Journal, 4/22).

David Newman-Toker, an associate professor of neurology at Johns Hopkins and the study's lead author, said, "Overall, diagnostic errors have been underappreciated and under-recognized because they're difficult to measure and keep track of owing to the frequent gap between the time the error occurs and when it's detected" (McKinney, Modern Healthcare, 4/22).

Although hospitals are required to report on certain quality measures, diagnostic errors are not reported or measured.

Newman-Token argued that more testing would not resolve the issue. He noted that 40% of emergency department patients complaining of dizziness receive a CT scan, which he said costs a total of about $500 million and is typically "useless" in determining the cause (Washington Post, 4/22).

Nonetheless, fear of malpractice suits for a missed diagnosis is a major driver behind "defensive medicine," the study noted (Wall Street Journal, 4/22).