Soldiers often have delayed reactions to traumatic events that may take years to manifest. Post-traumatic stress disorder occurs in five to 25 percent of service members who have been deployed to combat zones, with combat frequency and intensity being the strongest predictor of the condition, according Army Medical Command Policy Memo 12-035 (Apr. 10, 2012), Policy Guidance on the Assessment and Treatment of Post-Traumatic Stress Disorder. The policy advocates standardizing the diagnosis and care of Soldiers suffering from PTSD. Pictured here are Soldiers on an operation in Dora, Iraq, in June 2007.