Changes in intolerance of uncertainty over the course of treatment predict posttraumatic stress disorder symptoms in an inpatient sample

Intolerance of uncertainty (IU) is the inability to tolerate distress that arises in response to the absence of important information. The level of IU has been investigated across various psychological disorders; however, few studies have examined IU in trauma‐affected samples. We aimed to investigate the relationship between IU and posttraumatic stress disorder (PTSD) across the course of treatment. Participants (n = 106) had a diagnosis of PTSD and were from first responder, military, and occupational injury backgrounds. Participants completed self‐report questionnaires pre‐ and post‐engagement in an inpatient group trauma‐informed psychoeducation and skills (TIPS) intervention. Regression analyses indicated that decreases in overall and inhibitory IU were associated with decreases in PTSD severity overall and at the symptom cluster level. However, prospective IU was only associated with changes in the re‐experiencing, avoidance, and arousal PTSD symptom clusters. Our findings are congruent with the nascent literature indicating that IU may be a maintaining factor for PTSD, suggesting clinical relevance for attendance to IU within the course of treatment.