About 15 percent of 4,639 students sampled three or four months after the shooting reported posttraumatic stress disorder
(PTSD) symptoms, a lower overall rate compared with other school shootings, said Michael Hughes, Ph.D., a professor of sociology
at Virginia Tech, and colleagues in an article published online July 18 in Psychological Trauma. His coauthors included psychiatrist Robert Pynoos, M.D., M.P.H., a professor in the Department of Psychiatry and Biobehavioral
Sciences at the University of California at Los Angeles, and psychiatric epidemiologist Ronald Kessler, Ph.D., a professor
of health care policy at Harvard Medical School.