Reliability
Internal consistency is adequate for the PPI-R Total score and the PPI-R Content scale scores, with coefficient alpha ranging from .78-.92 for the community/college sample. For the offender sample, internal consistency estimates for the Total and Content scale scores ranged from .72-.84.
Temporal stability of PPI-R Total and Content Scale scores ranged from .82-.93 for a sub-set of the community/college sample over an average test-retest period of 19.94 days.
Validity
Evidence for construct validity of the PPI-R also was obtained via significant correlations with Hare's Self-Report Psychopathy Scale-II (SRP-II) Total score and Levenson's Self-Report Psychopathy Scale primary and secondary psychopathy scores in the community/college and offender samples.
Evidence of construct validity was also obtained via significant correlations between the PPI-R and self-report measures of pathological and nonpathological personality functioning, DSM-IV™ Antisocial Personality Disorder, interpersonal problems, sensation-seeking, substance use and offense variables.
Exploratory factor analyses using the community/college sample yielded a three-factor model of psychopathology: Self-Centered Impulsivity, Fearless Dominance and Coldheartedness.