Introduction: Dysfunctional appraisals about traumatic events and their sequelae are a key mechanism in posttraumatic stress disorder (PTSD). Experimental studies have shown that a computerized cognitive training, cognitive bias modification for appraisals (CBM-APP), can modify dysfunctional appraisals and reduce analogue trauma symptoms amongst healthy and subclinical volunteers. Objective: We aimed to test whether CBM-APP could reduce dysfunctional appraisals related to trauma reactions in PTSD patients, and whether this would lead to improvements in PTSD symptoms. Methods: We compared CBM-APP to sham training in a parallel-arm proof-of-principle double-blind randomized controlled trial amongst 80 PTSD patients admitted to an inpatient clinic. Both arms comprised a training schedule of 8 sessions over a 2-week period and were completed as an adjunct to the standard treatment programme. Results: In intention-to-treat analyses, participants receiving CBM-APP showed a greater reduction in dysfunctional appraisals on a scenario task from pre- to posttraining (primary outcome) assessments, compared to those receiving sham training (d = 1.30, 95% CI 0.82–1.80), with between-group differences also found on the Posttraumatic Cognitions Inventory (PTCI; d = 0.85, 95% CI 0.39–1.32) and the PTSD Checklist for DSM-5 (PCL-5; d = 0.68, 95% CI 0.23–1.14), but not for long-term cortisol concentrations (d = 0.25, 95% CI –0.28 to 0.78). Reductions in dysfunctional appraisals assessed via the scenario task correlated with reductions on the PTCI, PCL-5, and hair cortisol concentrations from pre- to posttraining time points. Conclusions: Results support dysfunctional appraisals as a modifiable cognitive mechanism, and that their proximal modification transfers to downstream PTSD symptoms. These findings could open new avenues for improving present therapeutic approaches.
Positive imagery cognitive bias modification (CBM) and internet-based cognitive behavioural therapy (iCBT): A randomized controlled trial
