Screening Test Items for Differential Item Functioning

A method for medical screening is adapted to differential item functioning (DIF). Its essential elements are explicit declarations of the level of DIF that is acceptable and of the loss function that quantifies the consequences of the two kinds of inappropriate classification of an item. Instead of a single level and a single function, sets of plausible levels and plausible functions may be declared. Some extensions are outlined, and a simulation study is presented.