We examined sudden, large, and stable shifts in symptoms from one therapy session to the next in two treatments for posttraumatic stress disorder (PTSD). Shifts in a positive direction (sudden gains) have so far been more frequently analyzed than those in a negative direction (sudden losses). We analyzed data from 102 outpatients suffering from PTSD who received either a cognitive-behavioral or a Gestalt-based intervention. Sudden gains, at 22.5%, were more frequent than sudden losses (3.9% of patients). Participants who had experienced sudden gains had lower PTSD scores at posttreatment, but not at the 6-month follow-up. As sudden losses were so rare, they were not analyzed statistically. Sudden gains accounted for 52% of overall treatment gains or 26% of overall change in a positive direction. Among very successful patients, those with sudden gains were overrepresented, but in absolute terms, there were as many patients without sudden gains in this group. There was no connection between sudden gains and type of intervention or depressive symptoms. Sudden gains and sudden losses occurred in our sample of PTSD patients, but in the light of current results, their clinical importance seems to be limited.

Year of Publication
Behaviour Research and Therapy
Number of Pages
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