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Based on initial Scholastic Aptitude Test (SAT) Verbal pretest data and hypotheses advanced in the research literature, 7 sentence completion and 16 analogy items with extreme levels of differential item functioning (DIF) were selected and then systematically revised and re-administered in an attempt to reduce or eliminate DIF. The apparent success of the effort makes similar attempts worth continuing. The particular terminology used in stems and keys, rather than the underlying skill being measured, seemed to be a recurring source of DIF in the SAT-Verbal items. Larger sample sizes, especially for minority focal groups, would help to stabilize the DIF categories used by Educational Testing Service (ETS) test developers. In addition, because the ETS delta metric is unbounded at the extremes, the use of both the Standardization (p-metric) and Mantel-Haenszel (delta-metric) methodologies is recommended for classifying the level of DIF for very easy and very difficult items. Further research is suggested to study the possible relationship between DIF and predictive validity. Nine tables and four figures present analysis results. An appendix summarizes DIF hypotheses. (Contains 26 references.) (Author/SLD)

This study was conducted to attempt to verify findings from an earlier study by I. M. Lawrence, W. E. Curley, and F. J. McHale (1988) in which differential item functioning (DIF) was examined for females on Reading subscore items from four forms of the Scholastic Aptitude Test-Verbal (SAT-V). The specific focus of this research was on verifying the technical science hypothesis as a contributing factor to DIF for females on science reading comprehension questions and the true-science classification as a contributing factor to DIF for females on sentence completion items. The total male sample for 3 SAT forms was 311,517 and the total female sample was 357,941. Confirmatory evidence for the factors identified in the earlier study is not clear-cut in this study. For reading comprehension items, the presence of technical science material in a reading passage tends to make the corresponding items more difficult for females. However, some items associated with highly technical passages do not function differently for males and females. With respect to sentence completion items, there was partial support for the hypothesis that true-science items are more difficult for females. However, the limited number of items studied does not warrant statements about the differential functioning of sentence completion items. An appendix contains some sample technical science reading comprehension items. (Contains six figures, seven tables, and two references.) (Author/SLD)