Psychometric Limitations of the Center for Epidemiologic Studies-Depression Scale for Assessing Depressive Symptoms among Adults with HIV/AIDS: A Rasch Analysis.
posted on 2016-06-20, 00:00authored byCL Gay, A Kottorp, A Lerdal, KA Lee
The Center for Epidemiological Studies-Depression (CES-D) scale is a widely used measure of depressive symptoms, but its psychometric properties have not been adequately evaluated among adults with HIV/AIDS. This study used an item response theory approach (Rasch analysis) to evaluate the CES-D's validity and reliability in relation to key demographic and clinical variables in adults with HIV/AIDS. A convenience sample of 347 adults with HIV/AIDS (231 males, 93 females, and 23 transgenders; age range 22-77 years) completed the CES-D. A Rasch model application was used to analyze the CES-D's rating scale functioning, internal scale validity, person-response validity, person-separation validity, internal consistency, differential item functioning (DIF), and differential test functioning. CES-D scores were generally high and associated with several demographic and clinical variables. The CES-D distinguished 3 distinct levels of depression and had acceptable internal consistency but lacked unidimensionality, five items demonstrated poor fit to the model, 15% of the respondents demonstrated poor fit, and eight items demonstrated DIF related to gender, race, or AIDS diagnosis. Removal of misfitting items resulted in minimal improvement in the CES-D's substantive and structural validity. CES-D scores should be interpreted with caution in adults with HIV/AIDS, particularly when comparing scores across gender and racial groups.
Funding
This research was supported by a grant from the National
Institute of Mental Health (NIMH, 5 R01 MH074358). Data
collection was supported by the General Clinical Research
Center in the UCSF CTSA (1 UL RR024131).