More than half of medical malpractice lawsuits against emergency physicians involve allegations of diagnostic errors, according to a study by national medical liability insurer The Doctors Company published online April 13.

Darrell Ranum , vice president for patient safety and risk management for The Doctors Company, and his colleagues, analyzed 332 emergency medicine claims in the insurer’s database that were closed from 2007 to 2013. Most claims (57%) were diagnostic related; they included allegations of failure to establish a differential diagnosis, failure to order diagnostic tests, failure to address abnormal findings, and failure to consider available clinical information.

A key lesson from the study is the importance of a thorough differential diagnosis by emergency physicians, Dr. David B. Troxel , medical director for The Doctors Company said in an interview.

“Our hope is that as physicians review the findings of this study, they will scrutinize their own systems and processes and determine whether the weaknesses identified in the study exist in their organization,” Dr. Troxel said.

Among the other claims, 13% related to improper management or treatment, 5% claimed improper performance of treatment, and 3% alleged failure to order medication.

The study also analyzed top factors that contributed to patient injury in the ED. Problems with patient assessments, such as failure to address abnormal findings, were the most common contributor at 52%. Patient factors, such as physical characteristics and noncompliance, were the second-most-frequent contributor at 21%. Other factors were lack of communication among physicians (17%), poor communication between doctors and patients (14%), insufficient or lack of documentation (13%), and workflow/workload issues (12%). (Claims could have more than one contributing factor.)

The study shows how important strong communication is in the emergency department (ED), said Mr. Ranum. He pointed out one claim in which a patient’s vital signs had changed during the course of a visit. The changes were not communicated to the emergency physician, and he inappropriately discharged the patient. In another case, a patient’s history of overdoses was not conveyed during a patient hand-off, which resulted in an overdose that was not treated in a timely manner, he said.

Communication breakdowns between physicians and patients also can be catalysts for legal claims.

“Sometimes, we find that patients don’t always understand instructions,” Mr. Ranum said. “If patients don’t understand the communication from their providers or if patient receives inadequate information, such as in situations where you have a language barrier, you can have problems there as well.”

Other injury contributors, such as workflow problems, are difficult for emergency physicians to control alone, said Dr. Roneet Lev , director of ED operations for Scripps Mercy Hospital in San Diego.

“We are all struggling with the right balance of staffing and really dependent also on hospital staffing,” Dr. Lev said in an interview. “We’re able to control on the physician end, how many doctors are there, but we’re not in control of how many nurses are there, how many techs are there, how many secretaries are there. That’s a huge part of the workflow. [Physicians are] only a small piece of the bottleneck.”

The study provides helpful information that emergency physicians can use to assess their own systems, Mr. Ranum said.

“Sometimes physicians feel like we’re beating up on them because we parade this whole line of cases where in many [instances], a physician’s care was not adequate,” he said. “We recognize that the systems that are used in hospital emergency departments are complex systems. When those systems fail, there’s an increased chance that a patient will be harmed a result. When physicians read the study, we would ask that they look at their own situation and organization and say, ‘Could these problem occur here?’ And if so, we would encourage them to undertake review of their own processes.”

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