The measurement of psychopathy: dimensional and taxometric approaches

This article extends the debate over personality disorders as dimensional or taxonic phenomena to the study of psychopathy and relates this issue to questions surrounding whether behaviors or personality traits best represent psychopathy. Proponents of dimensional measurements of psychopathy consider personality traits to be important constructs of psychopathy, whereas proponents of taxometric measurements consider behaviors to be important characteristics of psychopathy. After a brief introduction to the measurement of psychopathy, taxometric and dimensional measurement techniques are explained, their assumptions addressed, and their strengths and weaknesses discussed. Empirical evidence for each technique is then critiqued, and methodological problems are described. It is argued that methodological problems of existing studies largely preclude conclusions regarding whether psychopathy is dimensional or taxonic. Suggestions for future research are provided to address some of these methodological limitations. This review informs readers about each measurement approach and identifies problems regarding the dimensional or taxonic measurement of psychopathy.