Marines

Insomnia is the Most Commonly Reported Symptom and Predicts Other Symptoms of Post-Traumatic Stress Disorder in U.S. Service Members Returning From Military Deployments

This study retrospectively reviewed records from current members of the U.S. military who had completed the PTSD Checklist (PCL) at 0 and 3-months after returning from deployments. Insomnia was the most commonly reported symptom of PTSD on the PCL and had the highest average severity scores.

2010
McLay, R. N.
Klam, W. P.
Volkert, S. L.