TY - JOUR
T1 - Patient Health Questionnaire-9
T2 - A clinimetric analysis
AU - Cosci, Fiammetta
AU - Christensen, Kaj Sparle
AU - Ceccatelli, Sara
AU - Patierno, Chiara
AU - Carrozzino, Danilo
PY - 2024
Y1 - 2024
N2 - Objective: The Patient Health Questionnaire-9 (PHQ-9) is a widely used self-report measure of depression whose psychometric properties were found to be merely acceptable. Insufficient attention has been devoted to its clinimetric validity, while its clinical utility is still debated, particularly for assessing depression severity. This is the first study to test the PHQ-9 construct validity and clinical utility based on clinimetric principles. Methods: An online survey of 3,398 participants was conducted. Item response theory models (Rasch and Mokken analyses) were used to assess the PHQ-9 validity and determine its clinical utility. Results: Fit to the Rasch model was achieved after adjusting the sample size. Items 2, 4, 6, and 9 over-discriminated, while items 1, 5, and 7 under-discriminated. Local dependency between items 2 and 6 was indicated. The PHQ-9 was not unidimensional. A Loevinger’s coefficient of 0.49 was found, indicating an acceptable level of scalability. Conclusion: The PHQ-9 is an instrument with potential clinical utility as an overall index of depression, mainly for screening purposes. Substantial revision, particularly in the wording of over-and under-discriminating items, is needed.
AB - Objective: The Patient Health Questionnaire-9 (PHQ-9) is a widely used self-report measure of depression whose psychometric properties were found to be merely acceptable. Insufficient attention has been devoted to its clinimetric validity, while its clinical utility is still debated, particularly for assessing depression severity. This is the first study to test the PHQ-9 construct validity and clinical utility based on clinimetric principles. Methods: An online survey of 3,398 participants was conducted. Item response theory models (Rasch and Mokken analyses) were used to assess the PHQ-9 validity and determine its clinical utility. Results: Fit to the Rasch model was achieved after adjusting the sample size. Items 2, 4, 6, and 9 over-discriminated, while items 1, 5, and 7 under-discriminated. Local dependency between items 2 and 6 was indicated. The PHQ-9 was not unidimensional. A Loevinger’s coefficient of 0.49 was found, indicating an acceptable level of scalability. Conclusion: The PHQ-9 is an instrument with potential clinical utility as an overall index of depression, mainly for screening purposes. Substantial revision, particularly in the wording of over-and under-discriminating items, is needed.
KW - depression
KW - patient-reported outcome measure
KW - PHQ-9
KW - Rasch analysis
KW - validity
UR - http://www.scopus.com/inward/record.url?scp=85191687988&partnerID=8YFLogxK
U2 - 10.47626/1516-4446-2023-3449
DO - 10.47626/1516-4446-2023-3449
M3 - Journal article
C2 - 38281157
SN - 1516-4446
VL - 46
JO - Brazilian Journal of Psychiatry
JF - Brazilian Journal of Psychiatry
M1 - e20233449
ER -