Boston ? Dr. James Wang says he tries to tell his patients when extra medical procedures aren’t necessary. If they insist, though, he will do it — not so much to protect their health as his own practice.

After being sued for allegedly failing to diagnose a case of appendicitis, Wang says he turned to what’s known as “defensive medicine,” ordering extra tests, scans, consultations and even hospitalization to protect against malpractice suits.

“You are thinking about what can I do to prevent this from happening again,” he said, adding that he did nothing wrong but agreed to a minor settlement to avoid a trial.

The practice is under scrutiny as Congress attempts to get an accurate price tag for the sweeping national health care overhaul. A pivotal floor vote on the Democrats’ bill could come as early as Saturday.

Doctors say the hidden costs of the tests along with malpractice insurance and lawsuit awards are major drivers behind the soaring cost of care. Trial attorneys say bad medicine, not lawsuits, is to blame.

The debate has split along party lines, with Democrats typically siding with lawyers groups and Republicans agreeing with doctors.

The feuding between doctors’ groups like the American Medical Association, who have long battled rising malpractice premiums, and trial attorneys, who say malpractice lawsuits discourage bad medicine, has made it tough to put an accurate price tag on the cost of the issues.

That, in turn, is hampering Congress from getting an accurate tally for any sweeping national health care overhaul as it seeks to balance those costs against expanded coverage.

Doctors say the price of defensive medicine and malpractice insurance accounts for up to 10 percent of health care spending. Lawyers say malpractice settlement costs amount to less than 0.5 percent of the $2.5 trillion spent each year on health care.

The cost of annual malpractice premiums can vary wildly depending on specialty, geographic location and insurance carrier.

Doctors practicing internal medicine, who typically have the lowest premiums, can pay as little as $3,375 in Minnesota and as much as $57,859 in Florida. Obstetricians and gynecologists, who typically have the highest premiums, can spend as much as $201,808 in Florida and as little as $20,626 in Minnesota, according to the Medical Liability Monitor, which tracks premiums costs.

And, doctors say, defensive medicine can also produce a snowball effect, with one unnecessary test leading to more unnecessary tests.