Health care spending: Study shows high imaging costs for defensive purposes

For many years now, some physicians have ordered specific diagnostic procedures that are of little or no benefit to a patient, largely to protect themselves from a lawsuit. Until now, however, efforts to actually measure defensive medicine practices have been limited primarily to surveys sent to physicians. Such surveys would simply ask whether or not that individual actually practiced defensive medicine.

"This is the first study we know of that looked at the actual practice decisions of physicians regarding defensive imaging in real time -- prospectively done," says John Flynn, MD.

Flynn, who is Associate Chief of Orthopaedic Surgery at Children's Hospital of Philadelphia, says that many lawsuits hinge on the plaintiff's lawyer's claim that the doctor should have ordered extra diagnostic testing. "And such a claim may be the driving force of so much of the defensive test ordering."

According to Flynn, 72 orthopaedic surgeons, who are members of the Pennsylvania Orthopaedic Society, voluntarily participated in this study, which included some 2,068 patient encounters throughout the state of Pennsylvania. Most patients in this study were adults. The study found that 19 percent of the imaging tests ordered were for defensive purposes. Defensive imaging was responsible for $113,369 of $325,309 (34.8 percent) of total imaging charges for this patient cohort, based on Medicare dollars. The overall cost of these tests was 35 percent of all imaging ordered because the most common test was an MRI, an imaging test which costs more than a regular X-ray.

One piece of this problem to remember, Flynn says, is that the legal environment that drives physicians to order additional tests has an effect on patients too, in a way that involves more than costs. "Patients are sometimes put through tests that maybe otherwise would not be ordered."

The finding from this research that surprised Flynn the most was that surgeons were more likely to practice defensively if they had been in practice for more than 15 years.

"This was counterintuitive," he says. "I thought that young doctors would come out of medical school immediately after training, be less confident because they weren't experienced, and order more defensive tests. Then, as they become more comfortable and confident after 10 or 20 years in practice, they would order many fewer tests."

"In fact, the opposite was true. We found that -- in Pennsylvania at least -- a surgeon's defensive nature gets worse over time. In this legal environment, orthopaedic surgeons order more imaging tests of a defensive nature, because over time they become more concerned that someone is going to second guess or sue them."

Flynn says that medical liability awards typically are given because of the severity of a bad outcome, and not necessarily because of negligence. In fact, a May 2006 study published in the New England Journal of Medicine (Studdert DM) showed that 37 percent of claims did not involve medical errors, and in 3 percent of claims, no injury occurred at all.

Flynn pointed to various studies that show that defensive medicine, in general, is quite prevalent. One such study in the June 2005 Journal of the American Medical Association (Studdert DM) reported that almost 93 percent of 824 physicians in Pennsylvania responding to a survey practiced defensive medicine.

"Ideally, as a next step, we would hope to try to get a broader national picture using this prospective practice audit methodology, so we could get a better sense of the true costs of defensive imaging in orthopaedics," says Flynn.

"Ultimately, if you had doctors from multiple specialties -- from OB/Gyn to Neurosurgery to Emergency Medicine -- do this type of practice audit, you could accurately quantify how much of our nation's healthcare resources are wasted on defensive medicine."