Tracking individualized stuck points in cognitive processing therapy: The amount of change matters.

Cognitive processing therapy (CPT) targets maladaptive beliefs called "stuck points," which are typically assessed using standardized measures (e.g., the Posttraumatic Cognitions Inventory [PTCI]). This study examined whether changes in person-specific individualized stuck points (ISPs) were associated with reductions in self-reported and clinician-rated posttraumatic stress disorder (PTSD) symptoms and whether ISPs predicted PTSD severity beyond general stuck points (GSPs) measured using the PTCI. Adults (N = 57) with PTSD received 1-week massed virtual CPT via one of two randomized controlled trials. ISPs were tracked, and ISP belief strengths were rated after every other session and at 1- and 3-month follow-ups. Linear mixed-effects models examined associations between ISP changes and self-reported (PTSD Checklist for DSM-5 [PCL-5]) and clinician-rated PTSD (Clinician-Administered PTSD Scale for DSM-5 [CAPS-5]) symptom reductions, adjusting for baseline depression, gender, age, and treatment condition. Participants showed large reductions in PTSD symptoms from baseline to 1-month follow-up, M_{PCL-5 reduction} = 29.4, d = 2.02; M_{CAPS-5 reduction} = 10.49, d = 0.72. Average ISP belief strength decreased by 50.2% during treatment and up to 1-month follow-up, d = 2.75. Higher numbers of ISPs also predicted reduced PCL-5 scores, p = .021, R² = .02. However, when controlling for PTCI score, ISPs no longer significantly predicted PTSD symptom change, ps = .352-.534, whereas PTCI scores remained significant predictors, p < .001. ISP reductions were associated with PTSD symptom improvements but did not predict outcomes beyond PTCI-assessed GSPs. Tracking ISPs may still be valuable for tailoring therapy and enhancing patient engagement.