(HealthDay News) -- At least 5 percent of American adults -- 12 million people -- are misdiagnosed in outpatient settings every year, and half of these errors could be harmful, a new study indicates.
The findings, from an analysis of data from several published studies, should lead to greater efforts to monitor and reduce the number of misdiagnoses that occur in primary care, said Dr. Hardeep Singh, at Baylor College of Medicine, and colleagues.
Primary care is given outside the hospital, such as in doctors' offices and outpatient clinics.
The researchers noted that most efforts to improve patient safety have focused on hospitalized patients and on issues such as medication errors, infections and falls. However, the researchers added, most diagnoses are made in outpatient facilities.
There have been no reliable estimates of how often misdiagnoses occur in outpatient settings, making it difficult to develop methods of reducing such errors, according to the authors of the study published online April 16 in the journal BMJ Quality & Safety.
The researchers' review of the published studies involving U.S. adults showed that outpatient facilities have a misdiagnosis rate of just over 5 percent, or about one in 20 patients. Applied to the U.S. population, that means that 12 million adults are misdiagnosed in outpatient settings each year, according to a journal news release.
The results should be used by patient advocates, health care organizations, policymaker and researchers to seek ways to reduce the number of such misdiagnoses, the study authors concluded.