Rasch analysis of a simplified Beck Depression Inventory

• Published in: Personality and individual differences Vol. 54; no. 4; pp. 530 - 535
• Main Authors: Sauer, Sebastian, Ziegler, Matthias, Schmitt, Manfred
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.03.2013; Elsevier
• Subjects: Adult and adolescent clinical studies; BDI; Beck’s Depression Inventory; Biological and medical sciences; Depression; Item response theory; Medical sciences; Mood disorders; Psychology. Psychoanalysis. Psychiatry; Psychometrics. Diagnostic aid systems; Psychopathology. Psychiatry; Rasch; Techniques and methods; Rasch; Depression; Beck’s Depression Inventory; Item response theory; BDI; Mood disorder; Human; Questionnaire; Beck's Depression Inventory; Depression Inventory Beck; Psychometrics; Rasch model
• ISSN: 0191-8869; 1873-3549
• DOI: 10.1016/j.paid.2012.10.025

► Rasch analysis supported the simplified Beck Depression Inventory (BDI-S19). ► A large sample, including several subsamples, supports the validity of the results. ► Clinicians can consider using the BDI-S19 as a clinically economical alternative. Depression is one of the most clinically relevant mood disorders, and many assessment instruments have been developed to measure it. Probably the most frequently used instrument is Beck’s Depression Inventory (BDI). The simplified BDI (BDI-S) is a more efficient version of the BDI that has been shown to be no less reliable or valid. As the BDI-S has not yet been subjected to rigorous tests of Item Response Theory, it is the aim of the present paper to conduct such an analysis using the Rasch model. This study subjected a simplified version of the BDI consisting of 20 items (BDI-S20) to a Rasch analysis in a sample of N=5,035 participants. The scale, minus one misfitting item (BDI-S19), yielded a good approximation to Rasch assumptions. Moderate differential item functioning (DIF) was present. It is concluded that the BDI-S19 is an internally valid instrument for assessing depression, although some room for improvement exists.