Reliability of reports of childhood trauma in bipolar disorder: A test-retest study over 18 months.

This study aimed to explore the reliability of self-reported trauma histories in a population with a diagnosis of bipolar disorder using the Childhood Trauma Questionnaire. Previous studies in other populations suggest high reliability of trauma histories over time, and it was postulated that a similar high reliability would be demonstrated in this population. A total of 39 patients with a confirmed diagnosis (Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, criteria) were followed up and readministered the Childhood Trauma Questionnaire after 18 months. Cohen's kappa scores and intraclass correlations suggested reasonable test-retest reliability over the 18-month time period of the study for all types of childhood abuse, namely, emotional, physical, and sexual abuse and physical and emotional neglect. Intraclass correlations ranged from r = .50 (sexual abuse) to r = .96 (physical abuse). Cohen's kappas ranged from .44 (sexual abuse) to .76 (physical abuse). Retrospective reports of childhood trauma can be seen as reliable and are in keeping with results found with other mental health populations.