The Development and Validation of the Successful Psychopathy Scale

Successful psychopathy is characterized by core traits of callousness and interpersonal manipulation associated with clinical definitions of psychopathy, whilst largely being successful or adaptive in daily life. Despite rising interest in the field, the construct is still not well understood, partially due to competing theoretical models and the lack of a well-validated measurement. Using theoretical literature and expert opinion, we developed and validated the Successful Psychopathy Scale (SPS) for use within the general population. The pilot study (N = 208) developed an initial item pool which was subjected to Deductive Rational Strategy, reliability testing and an Exploratory factor analysis on 51-items which indicated a 5-facet structure. Study 1 (N = 403) developed on the pilot structure using an extended item pool based on researchers’ theoretical knowledge and expert ratings conducted in the pilot in an independent sample. The finalized structure of the SPS was 6-facets representing the key domains within successful psychopathy; core psychopathic traits, risk taking, confidence, stress immunity, social potency, and manipulation. Rasch analysis was used to verify the most suitable candidate items for a reliable and valid SPS measure its shorter form. The final 54-item long form and 30-item short form versions were satisfied expectations of unidimensionality with minor modifications resolved by creating super-items. The final versions of the SPS were correlated in expected directions with existing measures of psychopathic traits, professional skills, and success expectancy.