Investigating Psychometric Properties of New Scale of Dark Tetrad

The purpose of this study was to investigate the psychometric properties of the new scale of the Dark tetrad scale. The research method was survey and the statistical population consisted of all students who educated at Mohaghegh Ardabili University during 2017-2018. A sample of 600 individuals (300 females and 300 male) were selected through a multistage cluster sampling method. Data from 30 individuals were excluded due to a defect in completing the questionnaire. To collect data, Assessment Sadistic Personality Scale (Plouffe et al., 2017), Dark Triad Scale (JoneS & Paulhus, 2014), Emotional Intelligence Test (Bradbury-Graves, 2005) and Short Form of the NEO Questionnaire (Costa, McCray, 1989) were used. In order to examine the reliability of the questionnaire, the internal consistency coefficient was used and also the validity of the questionnaire was assessed by divergent validity, exploratory factor analysis and first-order confirmatory factor analysis. All analysis was done using SPSS-25 and LISREL 8.8. The results of the internal consistency coefficient showed that this scale had the appropriate reliability (Cronbach's alpha coefficient for Machiavellianism was 0.82, narcissism 0.86, psychopathy 0.79 and sadism 0.77). Confirmatory Factor Fitness Indexes also show the appropriate validity of the scale (CFI = 0.95, RFI = 0.96, NNFI = 0.93, RMSEA = 0/060). Therefore, it can be said that this scale is an appropriate instrument for measuring the dark aspects of personality.