Heterogeneity in content and psychopathies: comment on Marcus et al.

Comments on the original article by Marcus et al. (see record 2011-23134-001). Marcus et al. report a fascinating set of meta-analyses examining the correlations of fearless dominance (FD), self-centered impulsivity (SCI), and coldheartedness (CH) with each other, other psychopathy factors, and personality variables from four important higher-order domains. Across these studies, the factors of the Psychopathic Personality Inventory (PPI; Lilienfeld & Widows, 2005) were essentially uncorrelated, raising questions about the precise nature of psychopathy. Their meta-analyses also demonstrated that there was significant heterogeneity of effect sizes across analyses. The form of the PPI and the nature of the populations from which the samples were drawn often explained the heterogeneity in the relationships between the PPI factors and criterion-related variables. However, in a point raised by the authors, the content of the measures subsumed within the personality analyses in particular might also account for some of the unexplained heterogeneity. In this commentary, I will focus first on potential facets of the higher-order factors of personality and psychopathy that might explain conceptually the heterogeneity of effect sizes.