SAN DIEGO (AP) — CT scans, MRIs and other pricey imaging
tests are often more for the doctor’s benefit than the patient’s, new research
confirms.

Roughly one-fifth of tests that bone and joint specialists
order are because a doctor fears being sued, not because the patient needs
them, a first-of-its-kind study in Pennsylvania
suggests.

The study comes a day after President Barack Obama began a
push to overhaul state medical malpractice laws as a way to reduce unnecessary
tests that drive up health care costs.

“This study is a glimpse behind the curtain of what’s
happening in a doctor’s mind,” said its leader, Dr. John Flynn of
Children’s Hospital
of Philadelphia. If
doctors sense you might second-guess them or cause trouble, “you could
potentially be risking more tests being done.”

Results were reported Wednesday at an American Academy of Orthopedic
Surgeons conference in California.

Patients expect the highest level of care and think this
means the most advanced technology, Flynn said. Many patients feel better when
a doctor orders lots of tests — until they get the bill.

Besides hurting your wallet and adding to health care costs,
unnecessary tests can expose people to radiation that accumulates over a
lifetime and can raise the risk of cancer. Ordinary X-rays are rarely a
concern, but an MRI, or magnetic resonance imaging scan, can cost $1,000 or
more. And super-sharp X-rays called CT scans involve relatively large radiation
doses.

Yet doctors often order tests they don’t really think a
patient needs because they fear being sued if the diagnosis was wrong or they
miss detecting a problem.

Previous studies of how often this happens have relied on
doctor surveys. This is the first one to enlist doctors in advance to track
their decisions over time.

It involved 72 orthopedic surgeons throughout Pennsylvania who tracked
tests they ordered on 2,068 patients, mostly adults, in ordinary office visits,
emergency rooms and other settings. Doctors checked a box saying a test was
either required for clinical care or done “for defensive reasons.”

Defensive imaging accounted for 20 percent of total tests —
11 percent of X-rays, 38 percent of MRIs, 33 percent of CT scans, 57 percent of
bone scans and 53 percent of ultrasounds.

Defensive medicine also accounted for 35 percent of costs,
nearly all of it from MRIs.

One example: a torn meniscus, a knee cartilage injury that
is a leading reason for knee surgery. Studies have shown that a doctor’s
judgment based on symptoms and an exam is even better than an MRI to diagnose
the condition. Yet patients hardly ever go to surgery without having the
imaging test, Flynn said.

Surprisingly, the study found that newer doctors were less
likely to be defensive.

“That’s counterintuitive,” Flynn said. “You
would expect when you’re new in practice, not as trustful of your clinical
judgment, you’d order more.”

Doctors who have been sued in the last five years were more
likely to order tests defensively, said Robert Miller, a Temple University
medical student who helped lead the study and presented the results at the
conference. The authors said similar studies are needed on defensive imaging in
other specialties.

Dr. Lawrence Wells, a Philadelphia
surgeon who participated in the study, said doctors learn to develop “a
radar” for problem patients.

“It’s disheartening” to be sued, he said.
“Someone’s accusing you of a bad outcome or a wrong,” and that can
affect how a doctor behaves the next time he sees a similar case.

Patients need to trust their doctor’s judgment on what is
needed, Wells said.

On Tuesday, Obama made a budget proposal that includes money
to help states rewrite malpractice laws. Possible measures include caps on
awards. The administration also has proposed health courts where specially
trained judges rather than juries would decide such cases.

Questions to ask about a medical test:

—Is it truly needed? How will it change my care?

—Have you or another doctor done this test on me before?

—Does the test involve much radiation and is there an
alternative that does not?

—How many images are needed?

—Do you have a financial stake in the machines that will be
used?