Analysis of Differential Item Functioning in the NAEP History Assessment

The Mantel‐Haenszel approach for investigating differential item functioning was applied to U.S. history items that were administered as part o f the National Assessment o f Educational Progress, On some items, blacks, Hispanics, and females performed more poorly than other students, conditional on number‐right score. It was hypothesized that this resulted, in part, from the fact that ethnic and gender groups differed in their exposure to the material included in the assessment. Supplementary Mantel‐Haenszel analyses were undertaken in which the number o f historical periods studied, as well as score. was used as a conditioning variable. Contrary to expectation, the additional conditioning did not lead to a reduction in the number o f DIF items. Both methodological and substantive explanations for this unexpected result were explored.