The traits of the dark triad (narcissism, psychopathy, and Machiavellianism) capture the individual differences in the aversive personality. The dark triad has shown significant relations with behaviors that affect people's lives. One of the best-known instruments to assess the dark triad is the Dirty Dozen. However, controversy continues over the use of one general dark triad score or, conversely, three different scores. This study aimed to investigate the factor structure of the Dirty Dozen across eight global regions. There were 11,477 participants in 49 countries grouped into eight regions. Different factor structures were studied using confirmatory factor analyses. Both the three-dimensional models and the bifactor models (symmetrical or traditional and non-symmetrical or bifactor-[S - 1]) showed a good fit to the data. The bifactor-(S - 1) models (with psychopathy or Machiavellianism as the reference factors) show adequate fit to the data, supported by the coherence of the factorial loadings and the bifactor indices. Regarding measurement invariance for both models, configural, metric, and scalar invariance were satisfied. The results indicate that it is not clear whether a psychopathy or Machiavellianism reference factor predominates in the Dirty Dozen. For both models, templates are provided to obtain standardized scores for applied researchers in the eight studied world regions until future studies offer a greater amount of validity evidence for this instrument.
Keywords: Dirty Dozen; bifactor-(S – 1); dark triad; measurement invariance; transcultural.