Detecting differential item functioning with multiple causes: A comparison of three methods

Abstract

Differential item functioning (DIF) often arises from multiple sources. Within the context of multidimensional item response theory, this study examined DIF items with varying secondary dimensions using the three DIF methods: SIBTEST, Mantel-Haenszel, and logistic regression. The effect of the number of secondary dimensions on DIF detection rates was investigated with several test conditions such as the percentage of DIF items, item loadings, the correlation between primary and secondary dimensions, and DIF magnitude. Results indicate that both the Mantel–Haenszel and logistic regression procedures performed effectively in detecting DIF when multiple secondary dimensions were present.

Keywords:

• Differential item functioning
• logistic regression
• Mantel–Haenszel
• multidimensionality

Acknowledgments

The author would like to thank H. Jane Rogers and Hariharan Swaminathan for their suggestions and comments on the research idea and earlier drafts of this article.

Disclosure statement

No potential conflict of interest was reported by the author.