WASHINGTON -- Increases in medical malpractice insurance rates in some states, including Pennsylvania, were due largely to high payoffs on legal claims, according to a congressional survey released yesterday.

In Pennsylvania, insurers faced a 70.9 percent increase in successful malpractice claims against doctors and other medical providers from 1998 to 2001, said the General Accounting Office, investigative arm of Congress.

"Losses on medical malpractice claims appear to be the primary driver of increased premium rates in the long term," the report states. "Such losses are by far the largest component of insurer costs."

But the report, which surveyed rates in seven states, notes that the increases varied greatly from state to state and across medical specialties. General surgeons in Florida, for example, faced a 75 percent rate increase from 1999 to 2002, but rates increased only 2 percent in Minnesota during the same period.

Pennsylvania is one of a dozen states in the country that does not cap the payout in jury awards for victims of medical malpractice seeking pain and suffering damages. The U.S. House this year passed legislation, endorsed by the White House, to cap non-economic jury awards at $250,000. But Senate Democrats killed the bill, maintaining that men, women and children who were grievously injured through medical errors should be entitled to seek the damages.

Close to 1,000 Pennsylvania doctors have left the state in recent years, in large part to avoid skyrocketing costs of malpractice insurance, according to the Pennsylvania Medical Society.