Some physicians, the report said, are retiring or moving to locations with lower premiums. In addition, the survey said, some providers are cutting back on high-risk services, such as delivering babies and certain types of surgery.

Last week, the American Medical Association said their analysis found that liability insurance costs are forcing physicians to leave their practices, limit services or relocate.

The AHA cites two factors for the premium increases. First, it said, the amount of money paid per liability claim is increasing. The median payment has increased by 58 percent since 1996, the survey said.

Second, the report said, insurance company investment income has declined, leading many companies to raise premiums. Compounding the problem is that some major insurers, such as St. Paul, are leaving the medical liability market.

The AHA noted that provider and insurer groups are calling for liability reform to address the rising costs. These reforms include elimination of joint and several liability, limits on non-economic damages, limits on the time allowed for filing claims, limits on attorney contingency fees, and penalties for frivolous lawsuits.

The group added that tort reform is receiving more support at the federal level, partly because some state constitutions prohibit certain types of reforms.

The medical liability issue affects the cost and quality of care, the survey said. Fearing lawsuits, providers may practice defensive medicine by ordering more tests than are medically justified, or take other administrative actions to reduce risk, according to the report.

The current legal environment also makes providers less willing to share information on medical errors, the AHA said, information which could be used to prevent future errors.