I Am > Trauma: Experimentally Reducing Event Centrality and PTSD Symptoms in a Clinical Trial

Event centrality has been one of the strongest predictors of PTSD symptoms. We attempted to experimentally reduce event centrality using a modified version of Acceptance and Commitment Therapy (ACT) in a sample of traumatized participants from a community outreach center. Relative to a control group, participants who received ACT evidenced significant decreases in PTSD symptoms, depression, and event centrality. A mediation analysis revealed that the effect of condition on PTSD symptoms was mediated by decreases in event centrality. Only the effect of condition on depression was still significant at six weeks posttreatment. This study is the first to manipulate event centrality and suggests that components of ACT may be effective at reducing event centrality.