Using multidimensional item response theory to develop an abbreviated form of the Italian version of Eysenck's IVE questionnaire

This work aims at developing an abbreviated form of the Italian version of Eysenck's Impulsiveness-Venturesomeness-Empathy (IVE) questionnaire. The work consists of two studies that were conducted on two different data samples (N=200, 314, respectively). In the first one, a multidimensional item response theory model was used to identify, among the 54 items of the IVE, 18 items (six for each of the three scales) with simple structure, absence of misfit and gender DIF, good discrimination and coverage of the latent trait continua. Reliabilities and latent trait estimates obtained through the three abbreviated scales largely resembled those of the corresponding full-length scales. The second study supported the validity of the abbreviated questionnaire: The three-factor structure was confirmed, and correlations between the abbreviated scales, other Eysenck's personality traits, and risk-taking behaviors were consistent with previous findings.