Institute of Work and Organizational Psychology.
Department of Educational Psychology.
Psychol Assess. 2022 Jun;34(6):595-603. doi: 10.1037/pas0001124. Epub 2022 Mar 31.
The PHQ-9 has become a measure of reference in depression research and clinical practice. However, the issue of the PHQ-9's unidimensionality has not been fully elucidated, and the usability of the PHQ-9's total score requires clarification. In this study, we examined the dimensionality, scalability, and monotonicity properties of the PHQ-9 as well as the scale's total-score reliability. We did so based on exploratory structural equation modeling (ESEM) bifactor analysis and Mokken scale analysis (MSA). We relied on a total of 58,272 participants (63% female; = 43, = 13) from 29 samples involving seven different countries (e.g., Germany, the U.S.) and five different languages (e.g., German, English). We found no concerning deviations from measurement invariance for our ESEM bifactor model, neither across samples nor across sexes, age groups, and languages. The PHQ-9 met the requirements for essential unidimensionality in the pooled sample and across sex-, age-, and language-based subsamples. In each case, the general factor was strong (e.g., factor loadings ranged from 0.725 to 0.893 in the pooled sample) and Omega Hierarchical values exceeded 0.900. The correlations between the general factor and the observed total scores were large (≥ 0.952). Our MSA, including multilevel MSA, revealed that the PHQ-9's scalability is satisfactory. No monotonicity violation was detected, suggesting that the scale's total score accurately orders respondents on the latent Depression variable. Total-score reliability was good. This study provides robust evidence that the PHQ-9 can be used as a unidimensional measure of depressive symptoms by researchers and practitioners. (PsycInfo Database Record (c) 2022 APA, all rights reserved).
PHQ-9 已成为抑郁研究和临床实践中的一种参考测量工具。然而，PHQ-9 的单一维度问题尚未得到充分阐明，PHQ-9 总分的可用性需要进一步明确。在这项研究中，我们通过探索性结构方程模型（ESEM）双因素分析和莫肯量表分析（MSA）检验了 PHQ-9 的维度性、可扩展性和单调性以及该量表总分的可靠性。我们共使用了来自 29 个样本的 58272 名参与者（63%为女性； = 43， = 13），这些样本来自 7 个不同的国家（如德国、美国）和 5 种不同的语言（如德语、英语）。我们发现，无论是在样本之间，还是在性别、年龄组和语言之间，我们的 ESEM 双因素模型都没有出现令人担忧的测量不变性偏差。PHQ-9 在汇总样本以及基于性别、年龄和语言的子样本中均符合基本单一维度的要求。在每种情况下，总因素都很强（例如，在汇总样本中，因子负荷范围为 0.725 至 0.893），ω层次值均超过 0.900。总因素与观察到的总分之间的相关性较大（≥0.952）。我们的 MSA，包括多层次 MSA，表明 PHQ-9 的可扩展性令人满意。未发现单调性违反，表明量表总分可以准确地对潜在的抑郁变量进行排序。总分的可靠性较好。这项研究提供了强有力的证据，表明 PHQ-9 可以作为研究人员和实践者评估抑郁症状的单一维度测量工具。（PsycInfo 数据库记录（c）2022 APA，保留所有权利）。
