Differential Outcome of a Therapeutic Community Program for Internalizing and Externalizing Personality Disorders: A Change in Cognitive Processes Mediates Symptom Improvement

The identification of transdiagnostic mediating processes involved in a therapeutic change and their relationship with personality can contribute to a better adjustment of a therapeutic technique, enhancing its effectiveness. In a sample of 158 adults diagnosed with personality disorder who complete an inpatient therapeutic community program for 6 months, the hypothesis of a differential reduction in symptom intensity according to the externalizer/intemalizer typology is tested, and cognitive variables mediating change are explored. A pre-post change (p = .000, eta(2)(p) = 50) is observed, along with a difference between externalizers and internalizers (p= .002, eta(2)(p) = .06), and an interaction effect (p = .037, eta(2)(p) = .03). The effect of personality type on symptom change (beta = .43, p = .009) is no longer significant when negative automatic thoughts and dysfunctional attitudes are considered as mediators (beta = .06, p = .549). Findings are discussed from the perspective of personality disorder as a vulnerability factor.