State efforts to discipline physicians, which had been growing in recent years, flattened out in the late 1980s, and the rate of disciplinary actions fell for the first time in 1989, a consumer advocacy group said yesterday.

The Public Citizen Health Research Group's annual review showed a slight increase in the number of actions against physicians -- from 1,489 in 1988 to 1,509 in 1989, the latest year for which records have been compiled. But since the number of doctors in practice also rose, the rate of actions dropped from 2.77 per 1,000 physicians to 2.64.

The group estimated that more than 100,000 people in the United States are injured or killed in hospitals every year because of physicians' negligence.

"The fact that most states fail to exert maximum possible effort to discipline these doctors is one of the most serious threats to the health of American patients," the report said.

In 1984, the states took 745 serious disciplinary actions -- license revocations, license suspensions or probations -- against doctors. This jumped to 1,089 the next year, rose 17 percent in each of the next two years to 1,489 in 1987 and then remained essentially the same for the next two years.

But these numbers "still aren't high enough to accurately reflect the frequency of behavior warranting disciplinary action," the report said. More than 570,000 physicians practice in the United States.

"The country as a whole is going backward, not forward, when it comes to protecting the public from physicians who commit serious acts of negligence, operate under the influence of drugs or alcohol or sexually assault patients," said Sidney Wolfe, director of the health group.

The numbers in the report are based on actions reported by the Federation of State Medical Boards.

Public Citizen lauded Missouri's efforts, which topped the list of states with a disciplinary rate of seven serious actions per 1,000 physicians. Missouri's state medical board is one of the few with programs to find negligent physicians rather than waiting for formal complaints to be filed.

Other states in the top 10 in 1988 that remained there in 1989 were Georgia, Iowa, Oklahoma, Mississippi, West Virginia and Colorado, according to the report.

At the bottom of the list is New Hampshire, which took no actions against physicians in 1989. Connecticut had the next lowest record, followed by North Dakota, Texas and Maryland.

The differences in the rates among the states is a measure of how serious a state is at disciplining errant doctors, not of the quality of a state's doctors as a whole, the report said.

It said residents of states with low discipline rates should be alarmed because "people in these states are much more likely than people in high-discipline states to be injured or killed by doctors still on the loose because they haven't been caught."