Differential Item and Differential Distractor Functioning Analyses on Turkish High School Entrance Exam

Test fairness is one of the most critical elements in creating assessments. Differential item functioning (DIF) and differential distractor functioning (DDF) analyses play complementary roles in justifying test fairness. This study aims to investigate the correct (i.e., DIF) and incorrect (i.e., DDF) response choices of students based on gender in a standardized high-stakes test administered in Turkey. Given the purpose of this study, the Math section of 2011 Turkish High School Entrance Exam was investigated. For DIF analyses, Mantel Haenszel and Logistic Regression methods were used. For DDF analyses, two odds ratio approaches under the two-parameter logistic-nested logit model and nominal response model were used. According to the findings, in 500 and 1,000 sample sizes, DIF was not detected, however, only a 2,000 sample size indicated significant DIF results. Five DIF items were observed among 20 items, where three out of those five DIF items also showed DDF