Psychopathic Personality Inventory
The Psychopathic Personality Inventory (PPI-Revised) is a personality test for traits associated with psychopathy in adults. The PPI was developed by psychologists Scott Lilienfeld (now at Emory University) and Brian Andrews to comprehensively index the personality traits without assuming particular links to anti-social or criminal behaviors. It is a self-report scale developed in non-clinical samples (e.g. university students) that can also be used as a continuous measure with clinical samples (including prisoners). It includes some measures to detect impression management or careless responding.
The PPI was revised in 2005 to become the PPI-R (Lilienfeld & Widows) and now comprises 154 items organized into eight subscales. The item scores have generally been found to group into two overarching and largely separate factors, plus a third factor which is mainly dependent on scores on the other two:
I: Fearless dominance. Involving social influence, fearlessness, stress immunity.
II: Impulsive antisociality/selfishness. Involving 'Machiavellian' egocentricity, Rebellious nonconformity, Blame externalization, Carefree lack of planning.
A person may score at different levels on the different factors, but the overall score indicates the global extent of psychopathic personality. Higher scores on factor I are actually associated with emotional stability and social efficacy, as well as reduced empathy. Scores on factor II are more associated with maladaptive tendencies — including aggressiveness, substance use problems, negative feelings and suicidal ideation. Nevertheless, scores on the two major factors tend to be only modestly correlated.
The Psychopathy CheckList Revised (PCL-R) is another assessment procedure, which was developed in and intended for forensic settings. An analysis of the two measures on community samples or prisoners indicates that they assess partially different concepts of psychopathy.
- Skeem, J. L.; Polaschek, D. L. L., Patrick, C. J., Lilienfeld, S. O. (15 December 2011). "Psychopathic Personality: Bridging the Gap Between Scientific Evidence and Public Policy". Psychological Science in the Public Interest 12 (3): 95–162. doi:10.1177/1529100611426706.
- Copestake, Sonja; Gray, Nicola S., Snowden, Robert J. (1 April 2011). "A comparison of a self-report measure of psychopathy with the psychopathy checklist-revised in a UK sample of offenders". Journal of Forensic Psychiatry & Psychology 22 (2): 169–182. doi:10.1080/14789949.2010.545134.
- Malterer, M. B.; Lilienfeld, S. O., Neumann, C. S., Newman, J. P. (1 December 2009). "Concurrent Validity of the Psychopathic Personality Inventory With Offender and Community Samples". Assessment 17 (1): 3–15. doi:10.1177/1073191109349743.