A Comparison of Exposure Therapy, Stress Inoculation Training, and Their Combination for Reducing Posttraumatic Stress Disorder in Female Assault Victims

Reviewed by
Priscilla Schulz, LCSW

from an article of the same title by:

Edna B. Foa, Constance V. Dancu, Elizabeth A. Hembree, Lisa H. Jaycox, Elizabeth A. Meadows, and Gordon P. Street, Medical College of Pennsylvania-Hahnemann University

Published:
Journal of Consulting and Clinical Psychology, 1999, V. 67 (2), 194-200

What questions does this study address?

The primary questions in the study are

1. Is treatment superior to being on a waiting list for reducing PTSD symptoms?
2. Would exposure therapy (PE) alone or stress inoculation training* (SIT) alone ameliorate symptoms of PTSD as well as a treatment that combined the two therapies?

*Note: This study modified SIT protocol by excluding elements it has in common with PE.

Why combine treatments?

Other combination treatments such as cognitive processing therapy (CPT) that combine education, cognitive restructuring and exposure techniques have shown effectiveness in reducing symptoms of PTSD and accompanying depression.

Why is this important?

Two major categories of PTSD treatments exist today: exposure therapies and anxiety management programs. This study uses prolonged exposure (PE) and stress inoculation training (SIT) to represent the two categories of treatment, respectively. Differences in effectiveness exist between PTSD treatments: in producing immediate and long-term improvements and in reducing symptoms of accompanying disorders such as anxiety and depression. Informed treatment planning for trauma survivors requires that clinicians understand the differences PTSD treatments produce when used alone or in combination.

How do the different treatments in the study work?

In prolonged exposure (PE) clients relive traumatic memories by recounting traumatic experiences in session. They are also taught how to confront situations in real life that are intensely distressing reminders of the trauma but which are realistically not dangerous or threatening.

Stress inoculation training teaches trauma survivors how to cope with anxiety using techniques such as relaxation training, cognitive restructuring and positive self-talk.

What did the study find?

Active treatment of posttraumatic stress disorder in female assault victims is superior to no treatment (waiting list condition) in reducing symptoms and improving quality of life in these trauma survivors.

More specifically, among treatment participants (PE, SIT or PE+SIT)

• 40 to 60% lost their PTSD diagnosis
• All scored significantly lower on measures of PTSD, anxiety and depression than the wait list clients
• All improved in general social functioning.

The study's results did not support the hypothesis that a combination treatment, PE+SIT, would be more effective than either treatment alone.

The study found that prolonged exposure (PE) treatment participants:

• Had significantly greater improvements on measures of anxiety than other treatment participants
• Scored significantly lower (i.e., improved more) than PE+SIT participants on measures of depression
• Tended to have lower scores on depression than SIT participants
• Tended to have greater reductions of PTSD symptoms than SIT or PE+SIT participants even though all reduced PTSD symptoms.

What else from this study might be important to treatment providers?

Treatment providers are cautioned to conclude overall PE superiority. Several factors in the present study may have elevated the effects of PE and suppressed the efficacy of the SIT and PE+SIT treatment conditions:

1. In this study, PE participants had a significantly lower dropout rate and more were employed than those in the other treatment groups. Employment status and lifestyle may affect commitment to completing a treatment regimen.
2. Elements of stress inoculation training (SIT) that are similar to PE were not used in this study to avoid confounding the two treatments. Modifying a clinically proven effective treatment may reduce its overall efficacy.
3. Duration of sessions was kept constant across all three, treatment conditions. Therefore, in the combined treatment, PE+SIT, procedures were abbreviated. Combined treatments may need longer session time to adequately cover therapy material: process emotions, teach skills and review therapy homework.

Reviewed by: Priscilla Schulz, LCSW, July 1999