Development and validation of a Rasch-derived CES-D short form

Area of Science:

• Psychometrics
• Mental Health Research
• Item Response Theory

Background:

• The Center for Epidemiologic Studies-Depression scale (CES-D) is widely used but lengthy.
• Classical test theory methods for developing short forms may not fully capture the complexity of depression.
• Item response theory (IRT) offers advanced psychometric properties for scale development.

Purpose of the Study:

• To develop and validate a Rasch-derived short form of the CES-D for efficient depression screening.
• To evaluate the psychometric properties and structural validity of the new short form.
• To explore the latent structure of depression using IRT and structural equation modeling.

Main Methods:

• Rasch analysis was employed to derive a short form from the full CES-D scale.
• Cross-validation was performed across independent samples to assess generalizability.
• Latent variable modeling, specifically structural equation modeling, was used to test the fit of depression models.

Main Results:

• A Rasch-derived short form of the CES-D was successfully developed.
• Cross-validation confirmed the utility and structural validity of the short form.
• A hierarchical, single-factor model demonstrated the best fit for both the full and short CES-D forms, suggesting a unified construct of depression.

Conclusions:

• The Rasch-derived CES-D short form is a valid and useful tool for depression screening in the general population.
• IRT-based scale development provides superior measurement properties compared to classical methods.
• The findings challenge existing conceptualizations of depression, advocating for a unified factor model and prompting reconsideration of interfactor relationships in depression research.