Differential Item Functioning Analysis of the Science and Mathematics Items in the University Entrance Examinations in Turkey

Abstract

This study is aimed to detect differential item functioning (DIF) items across gender groups, analyze item content for the possible sources of DIF, and eventually investigate the effect of DIF items on the criterion-related validity of the test scores in the quantitative section of the university entrance examination (UEE) in Turkey. The reason for DIF items in the UEE basically comes from subject matter related factors, cognitive skills measured, and item format characteristics. It seems that higher order cognitive skills and figural or graphical representations used in item content are the two sources of DIF for favoring male students, whereas routine algorithmic calculations could produce DIF against males. Among the factors considered, cognitive skills assessed by items seem the most effective factor in producing gender DIF. However, DIF items do not create a threat to the criterion-related validity of the quantitative section of the UEE. Consideration of the DIF items and gender differences as presented here serves to underscore the need to consider gender differences in item selection on any measure that is used for a similar purpose.