American, German, and international Jewish groups are denouncing a decision by a German medical association to give its top honor to a physician who was once a member of the Nazi Party.

Dr. Hans Joachim Sewering, 92, received the Guenther Budelmann Medal from the Professional Association of German Internists, a 25,000-member group, in recognition of his lifelong contribution to the medical profession.

But Jewish groups — including the Anti-Defamation League, the Simon Wiesenthal Center, and the Central Council of Jews in Germany — said the association turned a blind eye on the doctor’s past, specifically his alleged role in sending more than 900 disabled children to a Nazi euthanasia center during World War II.

The decision “to honor an accused war criminal, one who is alleged to have used medicine for harm, is an insult to those who suffered under the Nazis, and besmirches the international standing of your organization,” the national director of the Anti-Defamation League, Abraham Foxman, wrote in a letter sent yesterday to the association’s president, Dr. Wolfgang Wesiack. The award, given March 30, was reported this week in Der Spiegel.

But the medical association defended its decision.

In a statement, the group justified the award on the grounds that Dr. Sewering, who has admitted to being a Nazi Party member, was not a convicted war criminal. After the war, prosecutors determined that Dr. Sewering was a middle-ranking Nazi officer, and he was fined.

Dr. Wesiack said Dr. Sewering made decades-long contributions to the “freedom of the medical profession,” according to the Associated Press. Asked why Dr. Sewering was chosen for the award, Dr. Wesiack told Britain’s Daily Mail, “He deserved it.”

Previously, Dr. Sewering has acknowledged his Nazi past. “I was 17 in 1933 when I had to join the SS,” he told the New York Times in 1993.

But others dispute his account. Jewish groups said Dr. Sewering is responsible for transferring more than 900 disabled Catholic children to a “healing center” where they died in euthanasia experiments. He also has been accused of signing an order in 1943 that authorized the transfer of a 14-year-old mentally retarded girl to a euthanasia center where she was killed.

In 1994, the U.S. Department of Justice confirmed that it placed him on its immigration “watch list,” barring him from entering the country.

Some critics said Dr. Sewering has distorted his actions in order to distance himself from his Nazi background. “His entire career has been built on this lie,” the director of the Task Force Against Hate at the Simon Wiesenthal Center, Mark Weitzman, said.

The head of a German Jewish group said Dr. Sewering’s past is well-known.

“A person like him, who has a Nazi history, is not supposed to get such an award,” the general secretary of the Central Council of Jews in Germany, Stephan Kramer, said.

Mr. Kramer said the association failed in its responsibility to acknowledge the accusations against Dr. Sewering. “They are not responsible for what Sewering did, but they are responsible for uncovering and trying to make sure the public knows,” he said.