Old and new issues in differential item functioning (DIF): How to overcome current research conservatism?

In the context of differential item functioning (DIF), some issues have been pointed out more than 20 years ago, whereas other ones have appeared much more recently (often due to an incredible increase of available information). In addition, there is some uprising evidence that the topic of DIF is becoming less attractive for journal editors. Explaining the reasons for this lack of interest in DIF, and why it should be actively countered, are the main goals of this talk. Three specific issues will be discussed: (a) the supremacy of the Mantel-Haenszel method, (b) the problem of item purification, and (c) the identification of DIF among multiple groups. Some recent and ongoing research results will be discussed to highlight why DIF should not be left alone in the years to come.