What does the Beck Depression Inventory measure in chronic pain?: a reappraisal.

The Beck Depression Inventory (BDI) is widely used to document the prevalence of depression in suffers of chronic pain and in research designs about this population. Williams and Richardson (1993) initially posed the question, "What does the BDI measure in chronic pain?". Results from their study found 3 independent constructs, which differed somewhat from those obtained in analyses with other non-pain subsamples. In our reappraisal of the question, we used confirmatory factor analytic procedures to assess the dimensionality of the BDI. Specifically, we questioned whether a hierarchical model in which a second-level depression construct underlies 3 constituent first-level constructs is reasonable for the data. Our results, based on a sample of 247 chronic pain patients, corroborated the adequacy of this model. The first-level constituent constructs were labeled Negative Attitudes/Suicide, Performance Difficulty, and Physiological Manifestations and were conceptually similar to first-level constructs obtained with other subsamples. Furthermore, external psychological measures and selected questionnaire items were used to assess convergent and discriminant validity of scales operationalizing the factor-analytically derived constructs. With these analyses, we clarify the constituents of depression as measured by the BDI. The findings from this study have implications for more refined epidemiologic and clinical research with chronic pain patients.