WASHINGTON, D.C. ? A painstaking reanalysis of data collected in the 1980s from Vietnam War veterans confirms that post traumatic stress disorder is a real and common psychiatric consequence of war, but it comes to the controversial conclusion that significantly fewer veterans were affected than experts have thought.

The report’s suggestion that one in five Vietnam veterans had the syndrome at some point during the first dozen years after the war – as opposed to previous estimates as high as one in three – drew praise from some experts as a valuable reassessment of an issue made timely by fresh waves of disturbed veterans coming back from Iraq.

But other experts and some veterans groups criticized the study, published in today’s issue of the journal Science, saying it used criteria so narrow that it excluded many vets who should have been included.

Symptoms of the disorder include flashbacks, emotional numbness, hypervigilance and exaggerated startle responses that leave a person impaired after experiencing one or more traumatic events.