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ERIC Number: EJ1148269
Record Type: Journal
Publication Date: 2017-Aug
Pages: 18
Abstractor: As Provided
ISSN: ISSN-0049-1241
How Does Polytomous Item Bias Affect Total-Group Survey Score Comparisons?
Hidalgo, Ma Dolores; Benítez, Isabel; Padilla, Jose-Luis; Gómez-Benito, Juana
Sociological Methods & Research, v46 n3 p586-603 Aug 2017
The growing use of scales in survey questionnaires warrants the need to address how does polytomous differential item functioning (DIF) affect observed scale score comparisons. The aim of this study is to investigate the impact of DIF on the type I error and effect size of the independent samples t-test on the observed total scale scores. A simulation study was conducted, focusing on potential variables related to DIF in polytomous items, such as DIF pattern, sample size, magnitude, and percentage of DIF items. The results showed that DIF patterns and the number of DIF items affected the type I error rates and effect size of t-test values. The results highlighted the need to analyze DIF before making comparative group interpretations.
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Publication Type: Journal Articles; Reports - Research
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A
Grant or Contract Numbers: N/A