At least 22 U.S. service members committed suicide in Iraq last year, prompting concern among defense officials who describe the rate as elevated but not alarmingly high.

Soldiers accounted for 19 suicides, officials said yesterday. The tally included a spike in deaths in July that prompted the Army to dispatch a 12-member mental health assessment team to Iraq in September.

William Winkenwerder Jr., assistant secretary of defense for health affairs, said in an interview yesterday that military health officials have not discovered "any trend" or identified specific steps the Army could have taken that would have prevented the suicides. Nothing has been found, he said, "that tells us that there's more we might be doing."

Col. James K. Gilman, director of health policy and services for the Army surgeon general, said that July's spike in suicides caused "great concern" but that no obvious common factor has emerged linking the individual cases. July's high rate, he said, did not reappear.

"You don't see worsening over time," Gilman said. The findings of the mental health team sent to Iraq in September have not been publicly released, he said.

The 19 Army deaths represented a suicide rate of more than 13.5 per 100,000 troops, officials said, which is higher than the Army's average of 10.5 to 11 per 100,000 troops in recent years. The overall suicide rate in the 1.2 million-member, active duty military is about one-third lower than that of the civilian population of about the same age range, defense officials said.

One official who spoke on the condition of anonymity called suicides in Iraq "an issue of concern, not an epidemic" and said: "It certainly is not at the 'Oh, my God' stage or panic or anything. But when the Army saw the numbers start to go up, they took very swift action, and have been working very hard ever since."

The Army and the Marines have stressed suicide prevention since the Sept. 11, 2001, terrorist attacks, after suicides that officials say may be at least partly attributable to lengthy deployments in Afghanistan and Iraq.

The numbers last year run counter to experience in past conflicts, when military suicides dropped during times of combat, officials said. During those conflicts, officials thought the reduction could be linked to troops' preoccupation with surviving combat, and with their removal from domestic problems and other personal pressures.

Whatever the cause of the elevated number of suicides in Iraq, Gilman said, "we want to get the rate lower. These are soldiers, and we care about every one of them. We want to get inside the problem even more and try to drive the rate down, in Iraq and in the Army as a whole."

To date, the 22 suicides represent about 14 percent of 153 nonhostile deaths in Iraq since the war began in March. An additional 343 service members have been killed in combat, bringing the total number of dead to 496, the Pentagon reported yesterday.

Winkenwerder said the military has committed considerable resources to treating soldiers' mental health problems, with the Army deploying nine combat stress company detachments to Iraq. Each Army division in Iraq, he said, has a psychologist, a psychiatrist and a social worker, with an emphasis on trying to treat soldiers' stress problems as close to the front lines as possible.

"We believe they are being identified, they are being supported," Winkenwerder said. Of 10,128 service personnel transported out of Iraq for medical reasons since the war began, he noted, 300 to 400 have been for mental health problems.

As Winkenwerder expressed concern about suicides in Iraq during an interview with reporters, he said military doctors and medical personnel have proven more successful than ever in saving the lives of wounded service members.

Of 2,413 soldiers wounded in action as of Jan. 8, he said, about 37 were said officially to have "died of wounds" after arriving at a combat medical facility, a rate of about 1.5 percent. "That is stunning. It is remarkable. It has never been seen before," said Winkenwerder, a physician who became the Pentagon's top health official in late 2001 after serving as executive vice president of health care services for Blue Cross Blue Shield of Massachusetts.

He attributed the low rate of soldiers who died of wounds to a combination of high-tech body armor worn by all soldiers in Iraq, surgical teams much closer to the front lines than in previous wars, new clotting agents that help stop bleeding on the battlefield, and new, portable ultrasound devices to determine whether soldiers are bleeding internally.

"All of our people have been working on these things for years, and I think it all came to fruition" in Iraq, Winkenwerder said. "We're saving people."