Dimensionality in Pettigrew and Meertens' Blatant Subtle Prejudice Scale

In this study, we analyzed dimensionality for Pettigrew and Meertens’ Blatant and Subtle Prejudice Scale (1995). More specifically, we sought to verify two hypotheses: first, that the scale is one-dimensional, and second, that the difference in the items featured in the two subscales (blatant and subtle) is exclusively due to their different locations on the scale of the latent variable. Expressing the latter hypothesis in the language of the Item Response Theory measurement approach we expected items from the blatant subscale to be more difficult (they require a greater level of prejudice to be positively answered by persons) than those of the subtle subscale. To this end, we used two databases (N1 = 323; N2 = 268), which we analyzed through confirmatory factor analysis and the partial credit model. Results confirmed our hypotheses, and highlighted the usefulness of the Item Response Theory models in analyzing prejudice scales.