Survey: Doctors Order Imaging Tests ‘Defensively’
Some Doctors Say They Request MRIs and X-rays Because They Worry About Getting Sued
By Kathleen Doheny
WebMD Health News
Reviewed by Laura J. Martin, MD
doctor examins xray of dollar

Feb. 16, 2011 (San Diego) -- Doctors don't order imaging tests such as MRIs and X-rays only to zero in on a diagnosis. One in five tests is ordered to protect against lawsuits, according to a new survey of Pennsylvania orthopaedists.

The survey results were presented today at the 2011 annual meeting of the American Academy of Orthopaedic Surgeons.

The study offers "a glimpse behind the curtain of what's happening in your doctor's mind," says researcher John M. Flynn, MD, associate chief of orthopaedic surgery at Children's Hospital of Philadelphia.

"This is a phenomenon that's going on," Flynn says, and his findings echo those of other studies. In the Pennsylvania survey, the defensive tests made up 35% of the total testing costs, accounting for more than $113,000 of the $325,000 charged for the tests, Flynn found. Wasteful health care spending, including defensive imaging, is thought to account nationally for a third of all health care expenditures, according to Flynn.

"The higher message is for our society," he says. "How can we afford this?"
Defensive Imaging: A Closer Look

Members of the Pennsylvania Orthopaedics Society were mailed the survey, and 72 responded, says Robert Miller, a third-year medical student at Temple University who presented the results.

''Twenty five counties were represented, totaling 2,068 imaging orders, and 19% were ordered for defensive reasons," Miller says.

In all, 640 orthopaedists in Pennsylvania got the survey. The 72 who replied answered basic questions such as their practice location, years in practice, whether the practice was private or academic, and whether they had an orthopaedic sub-specialty.

They also reported if they had been sued, the number of times, and how recently.

On the report, they described the body part imaged and whether the test was required for clinical care or ordered for defensive reasons.

When the researchers looked at specific imaging tests, the percent of defensive tests sometimes went higher than the one in five overall. For instance, about 38% of MRIs -- much more expensive than X-rays -- were ordered for defensive reasons. Knee, spine, and shoulder were the most common areas imaged.

And about 41% of CT scans, 56% of bone scans, and 43% of ultrasounds were ordered for defensive reasons. Under 10% of X-rays were ordered for defensive reasons.

Doctors who had experienced a lawsuit in the last five years were more apt to do defensive imaging, not surprisingly.

But so were those who had been in practice more than 15 years, Flynn found, which may reflect a growing wariness that they will be sued.

Specialists were more likely to order defensive tests. While 20.1% of imaging tests ordered by specialists were described as defensive, 16.4% of those ordered by general othopaedists were.

The study has limitations, Miller says. ''There were only about 2,000 patient encounters," he says. And only a minority of doctors completed the survey.