DEVELOPMENT AND VALIDATION OF THE FACETED DARK TRIAD SCALE

Abstract

Psychopathy, narcissism, and Machiavellianism, aka the ‘Dark Triad’, are comprised of common facets from the broad domain of antagonism or dis-agreeableness (e.g., callousness, deceitfulness) as well as facets unique to each. Assessments of the Dark Triad have typically neglected facet-level measurement, instead adopting broad multi-dimensional scales. Rival conceptualisations of psychopathy, narcissism and Machiavellianism, and the sub-par psychometric properties of their most widely used measures, have made it difficult to develop a consolidated, integrated perspective of the Dark Triad. As a result, the literature remains unclear regarding the degree to which findings are substantive or reflect measurement idiosyncrasies. In contrast, three recent standalone scales (the Elemental Psychopathy Assessment; the Five Factor Narcissism Inventory; and the Five Factor Machiavellianism Inventory) developed using the basic trait approach (i.e., combining relevant facets from the Five Factor Model to assess higher-order constructs) avoid these issues and provide numerous important innovations. However, because they were developed separately, simultaneous use would be problematic due to their length and three forms of redundancy: (i) identical scales are used in multiple measures, (ii) almost identical scales with different labels are used in multiple measures, and (iii) there are numerous ostensibly different yet highly similar scales that stem from the same FFM facet. The unintended consequence of each form of redundancy is construct proliferation and implicit (rather than explicit) construct overlap, which exacerbates confusion and issues of Jingle-Jangle. This thesis describes a multi- study empirical integration of these measures to develop a single set of unique facets that can assess the Dark Triad. Study 1 consolidated the Elemental Psychopathy Assessment, Five Factor Narcissism Inventory, and the Five Factor Machiavellianism into a single measure: the Faceted Dark Triad (FDT) Scale. Study 2 examined the cognitive response processes that participants engage in when completing the FDT. Studies 3 and 4 examined the predictive validity of the FDT, finding that it evinces superior prediction compared to the measures it was derived from and existing composite measures of the Dark Triad. Study 5 completed the first phase of FDT validation by demonstrating its reliability. The FDT provides comprehensive and theoretically coherent assessment of the Dark Triad and demonstrates superior psychometric properties compared to other measures. This thesis concludes with a discussion of the primary theoretical and practical contributions made by the introduction of a new measure of the Dark Triad. It highlights the strengths and limitations of the thesis and presents several directions for future research for both ongoing validation of the FDT and for broader study of the Dark Triad.

Date of Award	20 May 2024
Original language	English
Awarding Institution	The University of Manchester
Supervisor	Paul Irwing (Main Supervisor) & David Hughes (Co Supervisor)