For two decades, psychologic debriefing has been widely used to offer emotional and practical support to victims of trauma in the belief that it enhances recovery and prevents later effects such as post-traumatic stress disorder (PTSD). One of the most common forms of debriefing is critical incident stress debriefing (CISD, or the Mitchell model), which uses a single session of up to three hours to lead a group of victims through a seven-stage process. The session is conducted within one week of the traumatic event. The efficacy of CISD is highly controversial. Much of the extensive literature on this topic concerns narrative reviews, and studies are difficult to compare because of variations in patient experience and differences in study methodology. Van Emmerik and colleagues conducted a meta-analysis of the efficacy of CISD in preventing PTSD and other psychopathology following trauma.
They searched electronic databases and performed manual searches of relevant journals and books to identify appropriate studies. Inclusion criteria included a single debriefing session undertaken within one month of the traumatic event and psychologic assessment of participants before and after the intervention. Outcomes were assessed for CISD-type interventions and non-CISD programs such as counseling, education, and other forms of group debriefing.
From the 29 studies identified, 22 were excluded because they failed to meet one or more of the inclusion criteria. Five of the remaining studies were randomized controlled trials, one was nonrandomized, and one had no control group. Six of the trials used individual debriefing, and one studied group debriefing. After statistical analysis, the effect sizes in preventing PTSD and other symptoms were calculated for CISD, non-CISD interventions, and no intervention (controls).
Over time, no intervention resulted in a medium reduction in PTSD and a small reduction in other symptoms. Interventions using CISD resulted in a small reduction in PTSD and other symptoms, whereas non-CISD techniques resulted in medium to large reductions in PTSD symptoms and a small to medium reduction in other symptoms.
The authors conclude that, despite its widespread use and intuitive appeal, CISD did not reduce symptoms following trauma and could be detrimental to victims. They speculate that these surprising results could be the result of interference with natural coping and healing mechanisms following major trauma. Alternatively, a selection effect could contribute to the results if only the most impaired victims were allowed to participate in the counseling sessions. Finally, they point out that although counseling may not prevent long-term consequences, modified techniques may help some victims adjust following major trauma.