First do no harm: Worsening or improvement after prolonged exposure


During the past years, PTSD treatment competencies raised tremendously due to the development and evaluation in randomized controlled trials. Exposure and cognitive restructuring techniques are basics of a variety of effective psychotherapies. Our symposium discusses challenges, possible shortcomings, implications, and new applications of efficacious techniques (e.g., using the internet).

First do no harm: Worsening or improvement after prolonged exposure: Despite a substantial body of research accumulated over the 15 years indicating that exposure therapy programs are highly effective in reducing PTSD symptom severity and associated anxiety and depression across a wide range of trauma populations, few therapists utilize this treatment. One reason offered by therapists for not providing this treatment is their concern that exposure therapy may result in symptom worsening among individuals with PTSD (Becker et al., 2003). The purpose of this study was to investigate the frequency of symptoms worsening and symptom improvement following Prolonged Exposure (PE), one particular exposure therapy protocol developed for use in the treatment of PTSD, across five separate treatment studies (Foa et al., 1991, 1999, in preparation; Resick et al., 2002; Rothbaum et al., in preparation) and to compare it with other forms of cognitive behavior therapy (stress inoculation training, cognitive processing therapy, EMDR) and waitlist controls. Preliminary results based on two of the five studies (Foa et al., 1999; in preparation) found worsening of PTSD symptom in less than 1% of participants completing active treatment (N = 162) and 8% of participants completing waitlist (N = 39). PTSD symptom improvement was found in 90% of participants completing cognitive behavior therapy (N = 149) compared to 36% participants completing waitlist.






Shawn Cahill
Edna Foa
Barbara Rothbaum
Patrick Resnick

Original Work Citation

Cahill, S., Foa, E., Rothbaum, B., & Resnick, P. (2004, November). First do no harm: Worsening or improvement after prolonged exposure. In Beyond RCT research: Evaluating common and new treatment components (A. Maercker & G. Berthold, Chairs). Symposium conducted at the International Society for Traumatic Stress Studies 20th Annual Meeting, New Orleans, LA



“First do no harm: Worsening or improvement after prolonged exposure,” Francine Shapiro Library, accessed August 8, 2020,

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