Personality Disorder–Related Beliefs and Big Five Traits across Psychiatric Diagnoses: A Cross-Diagnostic Study

The study aimed to examine the differences in personality disorder related beliefs and Big Five personality traits. These were analyzed across major psychiatric diagnostic groups. A cross-sectional research design was used. The sample consisted of 355 patients recruited from public hospitals and private psychiatric settings in Lahore. Participants had confirmed diagnoses of depressive disorders, anxiety disorders, obsessive–compulsive disorder, and somatoform disorder. Additional diagnoses included bipolar disorder, psychosis, and substance use disorders. Sociodemographic questionnaire, Urdu Personality Belief Questionnaire, and Urdu Big Five Personality Inventory-10 were used to collect data. The findings showed that personality belief patterns differed clearly across diagnostic groups. Each disorder was associated with specific maladaptive beliefs. Depressive and anxiety disorders were linked with avoidant and dependent beliefs. Bipolar disorder showed higher narcissistic beliefs. Psychosis was associated with paranoid and schizoid beliefs. Obsessive–compulsive disorder showed strong obsessive-compulsive personality beliefs. Substance use disorders were linked with antisocial tendencies. Personality traits also varied across groups. Higher neuroticism was observed in depression and anxiety. Substance use disorders showed lower conscientiousness and agreeableness. Bipolar disorder was associated with higher extraversion and openness. Obsessive–compulsive disorder was associated with higher conscientiousness. These findings highlight the importance of assessing underlying personality beliefs and traits in psychiatric conditions. Incorporating personality-focused approaches in treatment may improve case formulation and reduce relapse. This is especially important in settings where treatment is mainly symptom-focused.