As many as 150,000 missed diagnoses annually could result in considerable harm to patients, according to a study and editorial.
To determine what diseases providers missed and why, researchers reviewed medical records of diagnostic errors detected at a Veterans Affairs facility and a large private health system. Electronic health records were programmed to detect unexpected hospitalizations or emergency return visits after a primary care index visit from October 2006 through September 2007.
Results appeared online Feb. 25 at JAMA Internal Medicine.
From among 190 cases, 68 unique diagnoses were missed, with the most common being pneumonia (6.7%), decompensated congestive heart failure (5.7%), acute renal failure (5.3%), cancer (primary) (5.3%), and urinary tract infection or pyelonephritis (4.8%).
Reasons included a breakdown during patient-practitioner clinical encounter (78.9%), referrals (19.5%), patient-related factors (16.3%), follow-up and tracking of diagnostic information (14.7%), and performance and interpretation of diagnostic tests (13.7%). A total of 43.7% of cases involved more than one factor.
Breakdowns involving the patient-practitioner clinical encounter were most often mistakes (such as cognitive errors) related to the medical history (56.3%), the physical exam (47.4%), ordering diagnostic tests for further workup (57.4%), and failure to review previous documentation (15.3%).
Researchers noted two more documentation-related problems. First, no differential diagnosis was documented at the first visit in 81.1% of cases. Second, practitioners copied and pasted previous progress notes into the index visit note in 7.4% of cases, which contributed to more than one-third (35.7%) of errors.
Potential severity of injury associated with the delayed or missed diagnosis was classified as moderate to severe in 86.8% of cases (ratings of 4-8 on an 8-point scale), with a mode of 5 (considerable harm). There was a modal severity rating of 5 across all 5 processes.
Most of the errors involved missed diagnosis of a large variety of common conditions as opposed to either a few selected conditions or rare or unusual diseases, the researchers noted.
And, the two sites differed in what was missed, because the VA center employed predominantly internists who cared for older veterans who generally had more comorbidities, while at the integrated health center, family practitioners cared for an overall younger population.
The findings show that there's still a need for clinical examination skills in an age of electronic health records and team-based care, researchers noted.
"Although the current literature highlights isolated cognitive difficulties among practitioners (eg, biases) and various interventions have been suggested to improve diagnostic decision making (eg, the use of checklists or second opinions), few cognitive obstacles have been sufficiently examined in the complex 'real-world' primary care environment, and few interventions have been satisfactorily tested," the researchers wrote. "Using the lens of missed opportunities in care rather than errors, institutions could create a new focus on discovering, learning from, and reducing diagnostic errors."
An editorial noted that with more than half a billion primary care visits annually in the United States, there could be at least 50,000 missed diagnostic opportunities annually, "most resulting in considerable harm."
Generalized further, the editorial continued, autopsy-based estimates of hospital deaths from diagnostic errors and another half billion visits annually to non-primary care physicians suggest that more than 150,000 patients annually might have experienced misdiagnosis-related harm.
The editorial continued that improvements could include training physicians in the most effective use of computer-based diagnostic decision support tools, or enabling electronic health records to monitor diagnostic performance continuously and give timely, specific feedback to providers.
"One critical step toward this last approach would be mandatory, structured recording and coding of presenting symptoms, rather than simply diagnoses, in our electronic health record systems," the editorialist wrote. "This step alone, if consistently performed, would radically transform our ability to track and reduce diagnostic errors."