Publications & Resources

Exploring Differential Item Functioning on Science Achievement Tests

Aug 1998

Laura S. Hamilton and Richard E. Snow

This study explores methods for detecting gender-based differential item functioning (DIF) on 12th grade multiple-choice and constructed-response science tests administered as part of the National Education Longitudinal Study of 1988 (NELS:88). Several combinations of conditioning variables were explored for DIF detection on both tests, and results were supplemented with evidence from interviews of students who completed the test items. On both tests, DIF in favor of males was exhibited primarily on items that involved visualization and that called upon knowledge and experiences acquired outside of school. The findings revealed that neither content nor format alone explained the patterns of male and female performance, and that an investigation of response processes may provide valuable additional information about the nature of gender differences in science achievement.

Hamilton, L. S., & Snow, R. E. (1998). Exploring differential item functioning on science achievement tests (CSE Report 483). Los Angeles: University of California, Los Angeles, National Center for Research on Evaluation, Standards, and Student Testing (CRESST).