Personality traits were assessed using the Italian version (Terracciano, 2003) of the Revised NEO Personality Inventory (NEO-PI-R), which measures 30 facets, six for each of the five major dimensions of personality (Costa & McCrae, 1992). The 240 items are answered on a five-point Likert scale, from strongly disagree to strongly agree; scales are roughly balanced to control for the effects of acquiescence. In this sample, the NEO-PI-R showed good psychometric properties: internal consistency reliabilities for the five factors ranged from 0.80 to 0.87. The factor structure replicated the American normative structure at the phenotypic and genetic level (Pilia et al. 2006; Costa et al. 2007). Raw scores were converted to T-scores (M=50, SD=10) using American combined-sex norms (Costa & McCrae, 1992).
