Written exposure therapy could be a more efficient and less burdensome treatment approach to PTSD than cognitive processing therapy, a study in military service members suggests.

Despite requiring half as many treatment sessions, written trauma accounts led to similar improvements to symptom severity as standard therapy, the US researchers say.

In a small, randomised trial, the team assigned 169 military service members (mean age 34) with PTSD to either five weekly sessions of written exposure therapy or 12 twice-weekly sessions of cognitive processing therapy during a four-year period.

Participants were evaluated at baseline and at 10, 20 and 30 weeks after the first treatment session to track changes in symptom severity assessed via the Clinician-Administered PTSD Scale for DSM-5 (CAPS-5).