No Conclusive Evidence Defensive Medicine Works

Research shows that in six out of seven specialties, higher-spending physicians faced fewer malpractice claims, suggesting that defensive medicine might protect doctors from litigation. But there is no definitive cause and effect.

Physicians who spend more money and resources treating patients are less likely to face malpractice claims than their more frugal colleagues, a Harvard Medical School study shows.

Study lead author Anupam Jena, MD, an internist at Massachusetts General Hospital, and an associate professor of healthcare policy at Harvard Medical School, says the findings suggest that defensive medicine might protect "higher-spending physicians" from litigation, although there is no definitive cause and effect.

"We don't know whether or not higher-spending physicians are in fact motivated by defensive medicine, so we can't specifically say that this is defensive medicine at work," Jena says. "All we know is that it is higher spending doctors getting sued less than lower spending doctors."

Jena and his colleagues examined more than 18 million hospital admissions in Florida from 2000 to 2009 with data on the malpractice histories of the 24,637 physicians who treated those patients during their hospital stay. The study found that in six out of seven specialties, higher-spending physicians faced fewer malpractice claims, accounting for differences in patient case-mix across physicians.

Among internal medicine physicians, the 20% in hospital spending (approximately $19,000 per hospitalization) faced a 1.5% probability of being involved in a malpractice incident the following year, compared to 0.3% in the top spending quintile (approximately $39,000 per hospital admission).

"In addition, we found that if you follow the same physician over time and use that same physician as their own control, when that physician spent more, he or she was less likely to be sued than in years in which he or she spent less," Jena says.

"The last finding was in a specific case study of obstetrics, in which we found that doctors who perform more C-sections get sued less often. That is notably because C-sections have often been thought of as being in part defensively motivated in the United States."

Jena spoke with HealthLeaders Media last week about his study and what the findings suggest. The following is an edited transcript.

HLM: What prompted this study?

Jena: If you think about what doctors worry about most in their careers malpractice rises to the top of the list. We had done some work in The New England Journal of Medicine a few years back that showed that in high-risk specialties, 100% of physicians are sued by the end of their career. And even in low-risk specialties, 70% of physicians are sued by the end of their career. From a lifetime perspective, that means that malpractice is extraordinarily salient to the physician.

As a result of that salience, a number of studies over two decades have looked at defensive medicine, which is the ordering of tests and procedures and other medical services solely to reduce the risk of malpractice liability. That is a different issue than what I would call good deterrent medicine, meaning that if malpractice liability leads a doctor to more appropriately order screening colonoscopies to detect colon cancer, we wouldn't want to call that defensive medicine. That's actually the intended effect of the malpractice system. Whereas if there is additional ordering of tests and procedures but there is no benefit, then we think of it as being defensive medicine.

Either way, as long as there is an effect of spending on malpractice risk, it could help explain why it is that doctors are reluctant to reduce utilization in the face of healthcare reform efforts that are asking them to do so.

HLM: Does this study validate defensive medicine?

Jena: No! It suggests that defensive medicine might "work" but it is not conclusive evidence. This is the first study to even look at this question. For many years we have presumed that defensive medicine works, meaning that if doctors do more and spend more they're less likely to be sued. Yet, it is entirely plausible that malpractice claims actually stem from the patient-physician relationship as opposed to how many tests or procedures a doctor orders. It's not a foregone conclusion to find this negative association that we did.

Nonetheless, we do find that higher-spending doctors get sued less often than lower-spending doctors. It could be either because that higher-spending actually improves outcomes or reduces errors, which would reduce malpractice claims. Alternatively, it could be that higher spending signals to patients and others that a more exhaustive workup was done, and that is reassuring in a sense that it reduces malpractice claims. Of course, the big issues is we don't know why doctors who spend more do so. We don't know if it is defensively motivated. All we know is that if they spend more and they get sued less often.

HLM: Can we equate higher spending with better care?

Jena: From this paper we can't necessarily do that. The literature has varied thinking on this. Some studies will show that higher spending is not associated with better care. There are a number of other studies that show just the opposite. In fact, we have a paper underway now that shows that higher spending is associated with better care when we look at individual physicians.

HLM: What are some of the other limitations of this study?

Jena: We don't know the mechanism by which higher spending is associated with fewer malpractice claims. It could be that higher spending is again associated with higher quality of care. Or, it could be that higher spending is simply reassuring to patients, attorneys, judges, and juries, and that prevents malpractice claims. We just don't know what the mechanism of our findings are.

HLM: What can be done to reduce defensive medicine?

Jena: From a research perspective, we have to better understand the mechanisms involved. From a policy perspective, it is important to recognize that our ability to get doctors to reduce utilization in healthcare services has been somewhat limited in the last few years, even though we've been doing a lot to try to get them to do so.

There could be a trade-off that physicians have to make between lowering utilization, which is good for the healthcare system and could even be good for the patient, certainly good financially, against the potentially higher risk of malpractice.

HLM: Do you see a role for tort reform?

Jena:  If you live in an environment were almost all doctors are practicing defensive medicine,  then a change in tort reform may not have any effect because even in states where tort reforms exist or in states where the liability environment is "favorable" you still see physicians reporting that they practice defensive medicine.  It could be that tort reforms don't really reduce defensive medicine, but that doesn't mean that there is not a lot of defensive medicine already going on.

HLM: Why is malpractice such a hot-button issue for physicians?

Jena: What we most certainly cannot insure against are the non-financial costs of malpractice; the anxiety over being involved in a lawsuit, and the possibility that your name will be publicly recorded for having been sued and lost a malpractice case. All of these things are extraordinarily difficult. If you talk to a physician who's been sued, many of them will tell you it was the worst experience of their life.