Evidence That Legal Reforms Which Reduce Malpractice Risk Decrease Defensive Medicine


August 29, 2018

One of the first studies to investigate how medical malpractice reforms such as damage caps affect specific clinical decisions provides strong evidence that caps have inspired physicians to reduce utilizing an expensive and invasive cardiology test.

“Many experts believe that invasive tests and interventions are overused, with fear of malpractice liability a potential motivating factor,” says Ali Moghtaderi, PhD, MBA, an assistant research professor of Clinical Research and Leadership at the George Washington University (GW) whose research focuses on the role of financial incentives and malpractice risks on physicians' behavior.

In recent years, many states have adopted non-economic damage caps, which limit awards to compensate malpractice plaintiffs for “pain and suffering.” To evaluate the impact that such caps may be having, Moghtaderi and his colleagues at GW, Kaiser Permanente, Northwestern University, and the Universities of Colorado and Texas studied data from 75,801 physicians who ordered or performed two or more coronary angiographies between 2009 and 2013. The physicians in the study practiced in 29 states, including nine that that adopted damage caps between 2003 and 2005 and 20 states without caps. Approximately half of these physicians (36,647) operated in states with caps.

The group focused on tests for coronary artery disease, which is the leading cause of death in the United States. Chest pain and other symptoms suggestive of coronary artery disease are common symptoms exhibited by patients in both emergency departments and outpatient settings. However, diagnosing and treating coronary artery disease involves medical uncertainty, significant malpractice risk, and substantial cost.

“Because unrecognized coronary artery disease can have catastrophic outcomes, with missed acute myocardial infarction an important cause of malpractice lawsuits, physicians are understandably cautious in their testing and intervention decisions,” explains Steven A. Farmer, MD, PhD, of GW’s Center for Healthcare Innovation and Policy. “Unfortunately, coronary artery disease symptoms are variable and nonspecific, clinical guidelines for testing patients with suspected coronary artery disease symptoms are general, and test results can be ambiguous.” He says that clinicians must exercise judgment as to who should be tested, what test to use initially (definitive but invasive coronary angiography through left-heart or combined left- and right-heart catheterization [ie, angiography] vs a noninvasive stress test), and how to treat coronary artery disease once it is diagnosed.

Farmer, Moghtaderi, and their colleagues, including GW Milken Institute School of Health Professor Avi Dor, hypothesized that if physicians faced lower malpractice risk, they would be willing to tolerate greater clinical uncertainty involving coronary artery disease, including the risk of future adverse events that earlier diagnosis might have prevented. The team reasoned that physicians who were less concerned about their liability would be less likely to initiate testing for coronary artery disease with angiography rather than a noninvasive stress test; to progress patients from initial stress testing to angiography, and to refer patients with borderline coronary artery narrowing for percutaneous coronary intervention (PCI) or coronary artery bypass grafting.

What the team found fit with their hypothesis. As they wrote in their recent paper: “Following cap adoption, overall ischemic testing rates remained constant, but testing became less invasive, and revascularization through PCI, following initial testing, declined. These findings suggest that physicians are willing to tolerate greater clinical uncertainty in [coronary artery disease] testing if they face lower malpractice risk. Our confidence intervals are wide, but even their upper bounds suggest meaningful changes in clinical behavior.”

“Association of Medical Liability Reform With Clinician Approach to Coronary Artery Disease Management” was published in JAMA Cardiology.