Isolating Trait and Method Variance in the Measurement of Callous and Unemotional Traits

To examine hypothesized influence of method variance from negatively keyed items in measurement of callous–unemotional (CU) traits, nine a priori confirmatory factor analysis model comparisons of the Inventory of Callous–Unemotional Traits were evaluated on multiple fit indices and theoretical coherence. Tested models included a unidimensional model, a three-factor model, a three-bifactor model, an item response theory–shortened model, two item-parceled models, and three correlated trait–correlated method minus one models (unidimensional, correlated three-factor, and bifactor). Data were self-reports of 234 adolescents (191 juvenile offenders, 43 high school students; 63% male; ages 11-17 years). Consistent with hypotheses, models accounting for method variance substantially improved fit to the data. Additionally, bifactor models with a general CU factor better fit the data compared with correlated factor models, suggesting a general CU factor is important to understanding the construct of CU traits. Future Inventory of Callous–Unemotional Traits analyses should account for method variance from item keying and response bias to isolate trait variance.