Written Exposure Therapy Noninferior to Prolonged Exposure in PTSD Treatment

Written exposure therapy for PTSD demonstrated noninferiority to prolonged exposure therapy and exhibited significantly lower attrition rates.

Written exposure therapy is as effective as prolonged exposure therapy in reducing posttraumatic stress disorder (PTSD) symptoms in military veterans. These results suggest that written exposure therapy could overcome existing barriers to PTSD treatment in patients. These are the findings of a study published in JAMA Psychiatry.

In this randomized noninferiority trial, conducted between September 2019 and April 2022, a total of 178 veterans who were seeking treatment for PTSD were enrolled and randomly assigned to either written exposure therapy or prolonged exposure therapy. The written exposure therapy group (n=88) had 5 to 7 sessions of treatment that consisted of 30 minutes of writing-based imaginal exposure followed by therapist and client discussion and no between-session assignments. The prolonged exposure therapy group (n=90) had 8 to 15 sessions that included 40 minutes of imaginal exposure minutes and 50 minutes of in vivo exposure between sessions.

Researchers assessed the change in PTSD symptom severity using the Clinician-Administered PTSD Scale (CAPS-5) for Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) from baseline to the 10-, 20-, and 30-week assessments. Noninferiority was the primary aim of testing, defined as a less than 10-point mean difference in CAPS-5 scores between the 2 treatment groups.

Participants had to be United States military veterans, meet the DSM-5 PTSD criteria, and be on a stable dose regimen if they were taking psychotropic medication. Individuals with significant cognitive impairment, comorbid psychiatric disorders, at high risk for suicide, or currently undergoing psychotherapy for PTSD were excluded from the study.

[G]ood PTSD treatment outcomes can be achieved with fewer sessions and less exposure to trauma-related stimuli than previously assumed.

Of the total veterans included, the majority were men (75.3%; mean age, 44.97) and White (62.9%). There were no significant differences among treatment groups in terms of age, educational level, household income, gender, or ethnicity. Additionally, there were no significant differences in PTSD symptom severity at baseline (t176 = −0.59; P =.55).

In this study, written exposure therapy demonstrated noninferiority to prolonged exposure therapy at each assessment period. The mean difference in CAPS-5 scores between written exposure therapy and prolonged exposure therapy groups was:

  • -2.42 points (95% CI, -5.69 to 0.86) at 10 weeks,
  • 1.38 points (95% CI, -2.38 to 5.15) at 20 weeks, and
  • 0.25 points (95% CI, -3.90 to 4.40) at 30 weeks.

The largest between-condition effect size was observed at the 10-week assessment (Cohen d =0.23; 95% CI, −0.53 to 0.06), with written exposure therapy showing slightly improved PTSD scores compared with prolonged exposure therapy. Furthermore, dropout rates were significantly lower in the written exposure therapy group compared with the prolonged exposure therapy group (12.5% vs 35.6%; χ2 =12.91; Cramer V=0.27).

The researchers concluded, “Our findings add to the evidence that good PTSD treatment outcomes can be achieved with fewer sessions and less exposure to trauma-related stimuli than previously assumed.”

A major limitation of the study was that it was conducted during the COVID-19 pandemic. Participants experienced significant external stressors such as illness, death of family members, and unemployment, which could have influenced study outcomes. Additionally, most participants were men and all were military veterans, which may limit the generalizability of the study’s findings.

Disclosure: Multiple study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.


Sloan DM, Marx BP, Acierno R, et al. Written exposure therapy vs prolonged exposure therapy in the treatment of posttraumatic stress disorder: a randomized clinical trial. JAMA Psychiatry. Published online August 23, 2023. doi:10.1001/jamapsychiatry.2023.2810