Cognitive distortions and irrational beliefs in post-traumatic stress, anxiety, and depressive disorders.

This study examined the validity of PTSD by comparing the dysfunctional cognitions found in a PTSD group, a clinical group (anxiety or depression), and a nonclinical group. Subjects completed the Millon Clinical Multiaxial Inventory-II, the Impact of Event Scale, the Beck Depression Inventory, the State-Trait Anxiety Inventory, the Cognitive Error Questionnaire, and the Survey of Personal Beliefs. Results revealed that PTSD and clinical groups were significantly more depressed and anxious than nonclinical subjects. Unlike the PTSD group, only the clinical group endorsed more dysfunctional cognitions than the nonclinical group, which supports the uniqueness of the PTSD group as differing cognitively from clinical groups.