“…In the past decades many procedures for identifying items with differential functioning have been envisioned and several of these methods have been implemented in R (R Core Team 2016): The package difR (Magis, Beland, Tuerlinckx, and De Boeck 2010) includes eleven different indices for dichotomous items; the package lordif (Choi, Gibbons, and Crane 2011) implements a modified logistic regression algorithm that allows for both dichotomous and polytomous items using estimated sum scores or item response theory (IRT) abilities as the matching criterion; packages like mirt (Chalmers 2012), ltm (Rizopoulos 2006), lme4 (Bates, Mächler, Bolker, and Walker 2015), and eRm (Mair, Hatzinger, and Maier 2016;Mair and Hatzinger 2007) allow to test DIF using the likelihood ratio test through comparisons of multiple models; while packages like psychomix (Frick, Strobl, Leisch, and Zeileis 2012;Frick, Strobl, and Zeileis 2015), mRm (Preinerstorfer 2016), and psychotree (Komboz, Strobl, and Zeileis 2017;Strobl, Kopf, and Zeileis 2015), enable modeling and testing for test invariance using mixture Rasch models or through trees. A recent IRT parametric framework for detecting DIF that allows for detection for both dichotomous and polytomous items with unidimensional or multidimensional IRT models, known as the differential functioning of items and tests (DFIT) framework (Raju, Van der Linden, and Fleer 1995), was yet to be implemented.…”