Psychometric properties of the Beck Depression Inventory--second edition (BDI-II) in individuals with chronic pain

Given the high prevalence of depression in individuals with chronic pain and the negative outcomes associated with such comorbidity, the importance of assessing depressive symptoms is widely acknowledged by chronic pain specialists. The BDI-II is a commonly employed measure of depressive symptomatology at pain centres; however, little is known about its psychometric properties in this population. This study evaluated factorial validity, internal consistency, and gender invariance of the BDI-II in 481 patients with chronic pain. Four competing models of the BDI-II factor structure were examined and confirmatory factor analysis supported the conceptualization of depression as a singular latent construct, within a hierarchical factor structure consisting of three first-order factors--Negative Attitude, Performance Difficulty, and Somatic Elements. Factor structure, item-total correlations, and correlations between subscale means and subjective pain experience support the inclusion of somatic items despite concerns regarding their overlap with pain symptoms. Internal consistency was good. Mean total scores were in the moderately severe range. Given the evidence of partial measurement invariance, an examination of mean gender differences was warranted. In contrast to the general population, the average scores of women and men were similar. Overall, results support the construct validity and internal consistency of the BDI-II for assessing depressive symptoms in both women and men with chronic pain. Results support the appropriateness of computing a total score and/or subscale scores. These results impact chronic pain researchers and clinicians, particularly given current trends toward empirically supported assessment.