WASHINGTON (AP) — Old checklist for doctors: order that test, write that prescription. New checklist for doctors: first ask yourself if the patient really needs it.

Nine medical societies representing nearly 375,000 physicians are challenging the widely held perception that more health care is better, releasing lists Wednesday of tests and treatments their members should no longer automatically order.

The 45 items listed include most repeat colonoscopies within 10 years of a first such test, early imaging for most back pain, brain scans for patients who fainted but didn't have seizures, and antibiotics for mild- to-moderate sinus distress.

Also on the list: heart imaging stress tests for patients without coronary symptoms. And a particularly sobering recommendation calls for cancer doctors to stop treating tumors in end-stage patients who have not responded to multiple therapies and are ineligible for experimental treatments.

Dr. Christine Cassel, president of the American Board of Internal Medicine, said the goal is to reduce wasteful spending without harming patients. She suggested some may benefit by avoiding known risks associated with medical tests, such as exposure to radiation.

"We all know there is overuse and waste in the system, so let's have the doctors take responsibility for that and look at the things that are overused," said Cassel. "We're doing this because we think we don't need to ration health care if we get rid of waste." Her group sets standards and oversees board certification for many medical specialties.

The recommendations come at a time when American health care is undergoing far-reaching changes. No matter what the Supreme Court decides on President Barack Obama's health overhaul, employers, lawmakers, insurers and many doctors are questioning how the United States spends far more on medical care than any other economically advanced country and still produces mediocre results overall.

Until now, the health care system has rewarded doctors for volume. Now the focus is shifting to paying for results and coordination. That explains the urgency for doctors themselves to identify areas of questionable spending.

It's unclear how much money would be saved if doctors followed the 45 recommendations rigorously. Probably tens of billions of dollars, and maybe hundreds of billions over time. That would help, but come nowhere near solving, the problem of high health care costs.

The nation's medical bill hit $2.6 trillion in 2010. A major quandary for cost-cutters is that most of the spending is attributable to a relatively small share of very sick people. Just 5 percent of patients accounted for half the total costs among privately insured people, according to a recent study from the IMS Institute for Healthcare Informatics.

Dr. James Fasules of the American College of Cardiology said the goal is to begin changing attitudes among patients and doctors.

"We kind of have a general feeling that if you don't get a test, you haven't been cared for well," said Fasules. "That has permeated American culture now." The new advice isn't meant to override a doctor's judgment, Fasules added, but to inform and support decisions.

The recommendations will be circulated to consumers and doctors by a coalition calling itself Choosing Wisely, which includes employer groups, unions, AARP and Consumer Reports. Neither the insurance industry nor the federal government was involved in process.

Each of the nine medical societies submitted five tests or treatments they viewed as overused. Their work was coordinated by a foundation that's an offshoot of Cassel's group. Eight other medical societies are developing additional recommendations, Cassel said.

The medical societies don't have any power of enforcement, and fear of malpractice lawsuits may well prompt many doctors to keep ordering as many tests as ever.

Insurers will certainly take a close look at the recommendations, but what they do may be limited. That's because most of the questionable tests and treatments in the lists don't particularly stand out in the avalanche of bills processed daily by insurance companies.

Take a recommendation for no annual EKGs for low-risk patients with no heart symptoms. Dr. John Santa, director of the Consumer Reports Health Ratings Center, said he used to routinely order EKG's when he was a general adult medicine practitioner. EKGs cost $50 to $60. A medical assistant would do the tests, and it would take Santa just a couple of minutes to read them. Yet 2 percent to 3 percent of his income came from EKGs, enough to make a difference in a tight year.

"It's very difficult for an insurance company to tell the difference when an EKG is being used as a diagnostic tool and when it is being used as a screening test," said Santa. "It would probably cause more trouble for insurance companies."

The medical groups that participated are: American Academy of Allergy, Asthma & Immunology; American Academy of Family Physicians, American College of Cardiology, American College of Physicians, American College of Radiology, American Gastroenterological Association, American Society of Clinical Oncology, American Society of Nephrology, and American Society of Nuclear Cardiology.