The Dirty Dozen Scale
Psychological Scientists Peter Jonason and Gregory Webster developed a scale known as the Dirty Dozen (2010), which uses 12-items to identify key features of this “Dark” or Toxic Triad.
Here’s the 12 items
1. I tend to manipulate others to get my way.
2. I tend to lack remorse.
3. I tend to want others to admire me.
4. I tend to be unconcerned with the morality of my actions.
5. I have used deceit or lied to get my way.
6. I tend to be callous or insensitive.
7. I have used flattery to get my way.
8. I tend to seek prestige or status.
9. I tend to be cynical.
10. I tend to exploit others toward my own end.
11. I tend to expect special favors from others.
12. I want others to pay attention to me.
Each item is rated on a 7-point Likert-type scale based how much it applies to a person. Here’s the subscales:
Narcissism = 3, 8, 11, 12
Psychopathy = 2, 4, 6, 9
Machiavellianism = 1, 5, 7, 10
As you can see, scores could range from 12 to 84. Webster & Jonason (2013) examined the scale in samples totaling 1,014 college students. The second sample used the 7-point rating scale, which resulted in an overall item mean of 2.92 and SD of 1.07.
Overall alpha was .87. See Table 3 of their article for more details. Note that this is a general population college sample thus we would expect higher scores in clinical samples.
For a more recent meta-analytic review of various measures of the Dark Triad, see Muris et al., 2017 (reference below).
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Jonason, P. K., & Webster, G. D. (2010). The dirty dozen: A concise measure of the dark triad. Psychological Assessment, 22(2), 420-432. doi:10.1037/a0019265 [See Table 8 on page 429 for the list of the 12 items.]
Muris, P., Merckelback, H., Otgaar, H. & Meijer, E. (2017). The Malevolent Side of Human Nature: A Meta-Analysis and Critical Review of the Literature on the Dark Triad (Narcissism, Machiavellianism, and Psychopathy). Perspectives on Psychological Science, 12 (2), 183-204.
Webster, G. D., & Jonason, P. K. (2013). Putting the 'irt' in 'dirty': Item response theory analyses of the dark triad dirty dozen—an efficient measure of narcissism, psychopathy, and Machiavellianism. Personality and Individual Differences, 54(2), 302-306. doi:10.1016/j.paid.2012.08.027
Psychopaths and Leadership
Psychology’s Toxic Triad https://suttonpsychology.blogspot.com/2018/10/psychologys-toxic-triad-narcissism.html
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