Hospital Diagnostic Errors May Affect 7% of Patients

Diagnostic errors are common in hospitals and are largely preventable, according to a new observational study led by Anuj K. Dalal, MD, from the Division of General Internal Medicine at Brigham and Women’s Hospital and Harvard Medical School in Boston, published in BMJ Quality & Safety.

Dalal and his colleagues found that one in 14 general medicine patients (7%) suffer harm due to diagnostic errors, and up to 85% of these cases could be prevented.

Few Studies on Diagnostic Errors

The study found that adverse event surveillance in hospital underestimated the prevalence of harmful diagnostic errors.

“It is difficult to quantify and characterize diagnostic errors, which have been studied less than medication errors,” explained Micaela La Regina, MD, an internist and head of the Clinical Governance and Risk Management Unit at ASL 5 in La Spezia, Italy, to Univadis Italy. “Generally, it is estimated that around 50% of diagnostic errors are preventable, but the authors of this study went beyond simply observing the hospital admission period and followed their sample for 90 days after discharge. Their findings will need to be verified in other studies, but they seem convincing.”

The researchers in Boston selected a random sample of 675 hospital patients from a total of 9147 eligible cases who received general medical care between July 2019 and September 2021, excluding the peak of the COVID-19 pandemic (April-December 2020). They retrospectively reviewed the patients’ electronic health records using a structured method to evaluate the diagnostic process for potential errors and then estimated the impact and severity of any harm.

Cases sampled were those featuring transfer to intensive care more than 24 hours after admission (100% of 130 cases), death within 90 days of hospital admission or after discharge (38.5% of 141 cases), complex clinical problems without transfer to intensive care or death within 90 days of admission (7% of 298 cases), and 2.4% of 106 cases without high-risk criteria.

Each case was reviewed by two experts trained in the use of diagnostic error evaluation and research taxonomy, modified for acute care. Harm was classified as mild, moderate, severe, or fatal. The review assessed whether diagnostic error contributed to the harm and whether it was preventable. Cases with discrepancies or uncertainties regarding the diagnostic error or its impact were further examined by an expert panel.

Most Frequent Situations

Among all the cases examined, diagnostic errors were identified in 160 instances in 154 patients. The most frequent situations with diagnostic errors involved transfer to intensive care (54 cases), death within 90 days (34 cases), and complex clinical problems (52 cases). Diagnostic errors causing harm were found in 84 cases (82 patients), of which 37 (28.5%) occurred in those transferred to intensive care; 18 (13%) among patients who died within 90 days; 23 (8%) among patients with complex clinical issues; and 6 (6%) in low-risk cases.

The severity of harm was categorized as minor in 5 cases (6%), moderate in 36 (43%), major in 25 (30%), and fatal in 18 cases (21.5%). Overall, the researchers estimated that the proportion of harmful, preventable diagnostic errors with serious harm in general medicine patients was slightly more than 7%, 6%, and 1%, respectively.

Most Frequent Diagnoses

The most common diagnoses associated with diagnostic errors in the study included heart failure, acute kidney injury, sepsis, pneumonia, respiratory failure, altered mental state, abdominal pain, and hypoxemia. Dalal and colleagues emphasize the need for more attention to diagnostic error analysis, including the adoption of artificial intelligence–based tools for medical record screening.

“The technological approach, with alert-based systems, can certainly be helpful, but more attention must also be paid to continuous training and the well-being of healthcare workers. It is also crucial to encourage greater listening to caregivers and patients,” said La Regina. She noted that in the past, a focus on error prevention has often led to an increased workload and administrative burden on healthcare workers. However, the well-being of healthcare workers is key to ensuring patient safety.

“Countermeasures to reduce diagnostic errors require a multimodal approach, targeting professionals, the healthcare system, and organizational aspects, because even waiting lists are a critical factor,” she said. As a clinical risk expert, she recently proposed an adaptation of the value-based medicine formula in the International Journal for Quality in Health Care to include healthcare professionals’ care experience as one of the elements that contribute to determining high-value healthcare interventions. “Experiments are already underway to reimburse healthcare costs based on this formula, which also allows the assessment of the value of skills and expertise acquired by healthcare workers,” concluded La Regina.

This story was translated from Univadis Italy using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.