“…Furthermore, although the ICU was originally developed as a unidimensional measure of CU traits (an overarching CU factor containing three subfactors: unemotional, callousness and uncaring), this early proposed three-factor, as well as a three-factor bifactor model (Essau et al, 2006), received limited support in either community (Ciucci et al, 2014; Wang et al, 2017b, 2019) or delinquent samples (e.g., Kimonis et al, 2008) due to the poor overall fit of these models. Notably, the unemotional factor has been shown to have relatively poor psychometric properties, showing low reliability, poor factor loadings and inadequate correlations with external criteria (e.g., Essau et al, 2006; Kimonis et al, 2008; Byrd et al, 2013).…”