INTRODUCTION: Personality disorders (PDs) have been associated with a poor prognosis of Major Depressive Disorder (MDD). The aim of the current study was to examine cognitive vulnerability (i.e., dysfunctional beliefs, extremity of beliefs, cognitive reactivity, and rumination) that might contribute to this poor prognosis of patients with PD comorbidity.METHODS: 309 outpatients with remitted recurrent MDD (SCID-I; HAM-D17≤10) were included within two comparable RCTs and were assessed at baseline with the Personality Diagnostic Questionnaire-4(+) (PDQ-4(+)), the Dysfunctional Attitude Scale Version-A (DAS-A), the Leiden Index of Depression Sensitivity (LEIDS), the Ruminative Response Scale (RRS), and the Inventory of Depressive Symptomatolog...