1/3 of imaging costs defensive, study says

Pennsylvania research eyes orthopedics

Nearly 35% of all the imaging costs ordered for 2,068 orthopedic patient encounters in Pennsylvania were ordered for defensive purposes, according to study presented recently at the 2011 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS).

It is well known that physicians order 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 simply would ask whether or not that individual actually practiced defensive medicine, explains John Flynn, MD, associate chief of orthopedic surgery at Children's Hospital of Philadelphia and author of the study.

"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," Flynn says.

Many lawsuits hinge on the plaintiff's lawyer's claim that the doctor should have ordered extra diagnostic testing, and that claim is the driving force behind much of the defensive test ordering, he says.

Specifics of the study

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

The legal environment that drives physicians to order additional tests has an effect on patients too, in a way that involves more than costs, Flynn says. "Patients are sometimes put through tests that maybe otherwise would not be ordered," he says.

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. Flynn found that, in Pennsylvania at least, a surgeon's defensive nature grows worse over time. In this legal environment, orthopedic 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.

"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 orthopedics," Flynn says. "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 health care resources are wasted on defensive medicine."


• John Flynn, MD, Associate Chief of Orthopedic Surgery, Children's Hospital of Philadelphia. Telephone: (215) 590-1000.