Gonzalez Oscar, Pelham William E
University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
Arizona State University, Tempe, AZ, USA.
Assessment. 2021 Mar;28(2):446-456. doi: 10.1177/1073191120913618. Epub 2020 Apr 4.
When items in a screening measure exhibit differential item functioning (DIF) across groups (e.g., males vs. females), DIF might affect which individuals are "caught" in the screening. This phenomenon is common, but DIF detection procedures do not typically provide guidance on whether the presence of DIF will meaningfully affect screening accuracy. Millsap and Kwok proposed a method to quantify the impact of DIF on screening accuracy, but their approach had limitations that prevent its use in scenarios where items are discrete. We extend the Millsap and Kwok procedure to accommodate discrete items and provide functions to apply the procedure to the user's own data. We illustrate our approach using published screening information and evaluate the proposed methodology with a small simulation study. Overall, we encourage researchers to use empirical methods to evaluate the extent to which the presence of DIF in a screening measure materially affects screening performance.
当筛查指标中的项目在不同群体（如男性与女性）间表现出项目功能差异（DIF）时，DIF可能会影响哪些个体在筛查中被“检出”。这种现象很常见，但DIF检测程序通常不会就DIF的存在是否会对筛查准确性产生有意义的影响提供指导。米尔萨普和郭提出了一种量化DIF对筛查准确性影响的方法，但其方法存在局限性，无法用于项目为离散型的情况。我们扩展了米尔萨普和郭的程序以适应离散型项目，并提供了将该程序应用于用户自身数据的函数。我们使用已发表的筛查信息来说明我们的方法，并通过一个小型模拟研究对所提出的方法进行评估。总体而言，我们鼓励研究人员采用实证方法来评估筛查指标中DIF的存在对筛查性能产生实质性影响的程度。
