The effect of item reordering on psychometric properties and student achievement: The evidence from health technicians’ education

Abstract

Background and Objective:  The use of multiple test forms with different item and option orders is a common strategy to reduce cheating in large-enrollment educational settings. However, concerns remain regarding whether such structural modifications may affect psychometric properties and student achievement. This study examined whether altering the order of test items and response options influences test reliability, item characteristics, and student performance in health technician education programs. Methods: We used an experimental pretest–posttest control group design with 122 students enrolled in health technician education programs. We administered a 20-item multiple-choice biology achievement test in parallel forms that differed only in item order and response options. Psychometric properties were evaluated using KR-20 reliability coefficients, item difficulty indices, and item discrimination indices. We analyzed differences among test forms using analysis of variance (ANOVA) and two-sample Z-tests. In addition, students’ self-reported interest in biology and perceived prior knowledge were examined in relation to achievement outcomes. Results: No statistically significant differences were found among the test forms in reliability coefficients, item difficulty indices, item discrimination indices, or posttest achievement scores (p > .05). These findings indicate psychometric equivalence across the forms. In contrast, students reporting higher levels of interest in biology and stronger perceived prior knowledge achieved significantly higher scores than their peers (p < .01), with moderate-to-large effect sizes. Descriptive findings further showed that a considerable proportion of students reported low interest in biology (37.7%) and insufficient subject knowledge (77.7%). Conclusions: The findings suggest that structural modifications such as reordering test items and response options do not compromise measurement quality or student achievement. Instead, learner-related variables appear to play a more substantial role in academic performance. The study adds empirical evidence to the limited literature on test form equivalence in vocational health education contexts and supports using parallel test forms as a practical approach to enhancing examination security while maintaining psychometric consistency.