Hare Psychopathy Checklist

In contemporary research and clinical practice, Robert Hare's Psychopathy Checklist-Revised (PCL-R) is the psycho-diagnostic tool most commonly used to assess Psychopathy. Because an individual's scores may have important consequences for his or her future, the potential for harm, if the test is used or administered incorrectly, is considerable, so that the test should only be considered valid if administered by a suitably qualified and experienced clinician under controlled conditions.

PCL-R Model of psychopathy
The PCL-R is a clinical rating scale with 20 items. Each of the items in the PCL-R is scored on a three-point (0, 1, 2) scale according to specific criteria through file information and a semi-structured interview. A value of 0 is assigned if the item does not apply, 1 if it applies somewhat, and 2 if it fully applies.

The current edition of the PCL-R officially lists four factors (1.a, 1.b, 2.a, and 2.b).

PCL-R Factors 1a and 1b are correlated with narcissistic personality disorder and histrionic personality disorder. It is associated with extroversion and positive affect. Factor 1, the so-called core personality traits of psychopathy, may even be beneficial for the psychopath (in terms of nondeviant social functioning).

PCL-R Factor 2a and 2b are particularly strongly correlated to antisocial personality disorder and criminality and is associated with reactive anger, criminality, and impulsive violence.