Do self-criticism and somatic symptoms play a key role in chronic depression? Exploring the factor structure of Beck depression inventory-II in a sample of chronically depressed inpatients

Abstract

Background: The factor structure of depression differs for different sub-samples. The purpose of this study was to explore the factor structure of Beck Depression Inventory-II in patients with chronic depression presenting for inpatient treatment. Methods: Using exploratory structural equation modeling (ESEM), we explored whether a two-factor solution or a bifactor solution provided best model fit for a sample of 377 patients. For the best fitting model stability was assessed with tests for invariance across primary diagnosis (persistent depressive disorder v. recurrent major depressive disorder), and presence of comorbidity. Results: A bifactor solution with one general factor and two specific factors provided best model fit. Invariance analyses provided support for measurement invariance and stability of the factor solution. Limitations: The naturalistic study design implies some uncertainty regarding possible systematic differences between the patients on demographic and clinical characteristics. Conclusion: The factor structure in our sample was best explained by a general depression factor, one specific factor pertaining to self-criticism, and one consisting of the somatic items fatigue, disturbance of sleep, and appetite. Clinicians could benefit from paying special attention to the subfactors identified, as these findings may have implications for treatment choice for patients with chronic depression.