ASSESSING UNEXPECTED DIFFERENTIAL ITEM PERFORMANCE OF FEMALE CANDIDATES ON SAT AND TSWE FORMS ADMINISTERED IN DECEMBER 1977: AN APPLICATION OF THE STANDARDIZATION APPROACH1

A new approach to assessing unexpected differential item performance (item bias or item fairness) is developed and applied to the item responses of males and females to SAT/TSWE items administered operationally in December 1977. While the main body of the report describes the particulars of the present application and delineates the essential features of the approach, a technical appendix describes the standardization approach in detail. The primary goal of the standardization approach is to control for differences in subpopulation ability before making comparisons between subpopulation performance on test items. By so doing, it removes the contaminating effects of ability differences from the assessment of item fairness. Of the total of 195 items studied, the standardization approach identified only a handful as meriting careful review for possible content bias. Of these few, only one item exhibited a clearly unacceptable degree of unexpected differential item performance between males and females that could be attributed to content bias.