The German Version of the "Psychopathic Personality Inventory" (PPI) -: psychometric properties and validation of the authorized German version

Psychopathy is the most relevant predictor for an individual prognosis of delinquency. Until now, psychopathy was commonly assessed by use of the PCL-R (Hare, 1990/91) which is rather time- and staff-consuming. Therefore, a more economic instrument is quite desirable. The Psychopathic Personality Inventory (Lilienfeld & Andrews, 1996) is a self-report instrument to assess psychopathic personality traits which consist of ten subscales with a total of 187 items (8 subscales with 163 items and 2 validity scales with 24 items). The German version was applied to a sample of N = 290 subjects (N = 187 participants of a norm group and N = 103 undergraduates). The psychometric properties (reliability and validity) turned out to be very satisfactory with an internal consistency of alpha = .91 and a test-retest reliability (Pearson; interval of 12 weeks) of the PPI total score of r = .96. Moreover, gender differences for the total score as well as for the subscale scores were in the expected direction. Finally, convergent as well as discriminant validity could be demonstrated by use of the NEO-FFI and the Interaction-Anxiety-Questionnaire IAF. Although the factorial structure (tested with CFA and EFA) showed differences to the original version, the German version of the PPI can be considered to be a highly reliable and valid instrument.