Diagnostic error affects millions a year


Diagnostic errors—missed opportunities to make a timely or correct diagnosis based on available evidence—occur in about 5% of adults in the US, according to a new study published in the April 17 issue of BMJ Quality & Safety.

The study, partially funded by the Agency for Healthcare Research and Quality (AHRQ), estimates that approximately 12 million adults in the US could experience an outpatient diagnostic error each year.

Titled "The frequency of diagnostic errors in outpatient care: estimations from three large observational studies involving U.S. adult populations," the study used data from three previous studies of errors in general primary care diagnosis, colorectal cancer diagnosis, and lung cancer diagnosis.  In all three studies, diagnostic errors were confirmed through rigorous chart review.

The authors estimated that about half of the diagnostic errors they found could have severely harmed patients.
Diagnostic errors can harm patients by delaying their treatment. For example, a delayed or incorrect cancer diagnosis could make the disease harder to treat or more deadly.

"Keeping patients safe begins with a correct and timely diagnosis," said AHRQ director Dr Richard Kronick. "Diagnostic errors made in outpatient care can be difficult to measure, and this is a relatively new area for patient safety researchers.

"Health care professionals are typically accurate in making diagnoses, but finding ways to improve diagnoses and eliminate errors is an important goal. This study helps us better understand the extent of the problem and focus our efforts on reducing the harm to patients."

The findings of this study, led by Dr Hardeep Singh, are consistent with recent data from the general public about diagnostic errors. This study is significant because it is based on a large sample size and is the most robust estimate thus far to address the frequency of diagnostic error in routine outpatient care.

"Misdiagnosis is clearly a serious problem for the health care field," said Singh. "This population-based estimate should provide a foundation for policymakers, health care organizations and researchers to strengthen efforts to measure and reduce diagnostic errors."

BMJ Quality & Safety, US, AHRQ, Dr Richard Kronick, Dr Hardeep Singh