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Neither Cronbach’s Alpha nor McDonald’s Omega: A Commentary on Sijtsma and Pfadt

Published online by Cambridge University Press:  01 January 2025

Eunseong Cho Open the ORCID record for Eunseong Cho [Opens in a new window]
Eunseong Cho*
Affiliation:
Kwangwoon University
*
Correspondence should be made to Eunseong Cho, Republic of Korea College of Business Administration, Kwangwoon University, 20 Kwangwoonro, Nowon-gu, Seoul01897, Republic of Korea. Email: bene@kw.ac.kr
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Abstract

Sijtsma and Pfadt (2021) published a thought-provoking article on coefficient alpha. I make the following arguments against their work. 1) Kuder and Richardson (1937) deserve more credit for coefficient alpha than Cronbach (1951). 2) We should distinguish between the definition of reliability and its meaning. 3) We should be wary of overfitting in the use of FA reliability. 4) Our primary concern is to obtain accurate reliability estimates rather than conservative estimates. 5) Several reliability estimators, such as λ2\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\lambda _{2}$$\end{document}, μ2\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\mu _{2}$$\end{document}, congeneric reliability and the Gilmer-Feldt coefficient are more accurate than coefficient alpha. 6) The name omega should not be used to refer to a specific reliability estimator.

Keywords

coefficient alphacronbach’s alphatau-equivalent reliabilitycongeneric reliabilityclassical test theorycoefficient omega
Type
Revisiting Cronbach’s Alpha
Information
Psychometrika , Volume 86 , Issue 4: Special Section: Revisiting Cronbach’s Alpha , December 2021 , pp. 877 - 886
Copyright
Copyright © 2021 The Psychometric Society

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Footnotes

The present research was supported by the Research Grant of Kwangwoon University in 2020

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