The Hare Psychopathy Checklist-Revised (2nd edition, PCL-R) is a 20-item rating scale for the measurement of the clinical construct of psychopathy. Although it was designed for use in research, its explanatory and predictive features have led to its widespread use within the criminal justice system. This entry describes the development of the PCL-R, its psychometric properties, and its use in the criminal justice system.
The PCL-R had its origins in the late 1970s at a time when a variety of clinical and self-report methods were being used to define what ostensibly was psychopathy. There was little evidence that these methods were conceptually or empirically related to one another, with the result that many research findings obtained with one method could not be replicated with other methods. The development of the PCL-R (and its predecessor, the PCL) was based on a rich clinical tradition that included the writings of, among others, Benjaman Karpman, Silvano Arieti, William and Joan McCord, and, especially, Hervey Cleckley. The selection of several items and the scoring protocols was influenced by the nature of the population with which the research was being conducted, namely incarcerated offenders. Prison populations continue to offer several advantages for the study and measurement of psychopathy: high prevalence and the availability of extensive amounts of “hard” information about the individual. The latter is particularly important, given that self-disclosed information (e.g., interviews, self-reports) typically is subject to impression management and often unreliable, not only in offenders but also in the general population.
The PCL-R scoring criteria first were distributed to researchers in 1985. With the subsequent accumulation of large amounts of empirical data, the criteria and accounts of the psychometric properties of the PCL-R were formally published in 1991. This was followed by a dramatic upsurge in the use of the instrument for both basic research and applied (clinical, forensic) purposes and the publication of a greatly expanded second edition in 2003, which contains data on more than 10,000 offenders and forensic psychiatric patients. Throughout, the scoring criteria have remained unchanged to ensure conceptual and measurement continuity.
PCL-R Description and Psychometric Properties
The PCL-R uses a semistructured interview, case history information, and specific scoring criteria to rate each item on a 3-point scale (0, 1, 2) according to the extent to which the criteria are judged to apply to a given individual. Total scores can vary from 0 to 40 and reflect the degree to which the individual matches the prototypical psychopath.
There is good evidence that the PCL-R is a very reliable instrument when administered and scored by trained and experienced raters. Internal consistency is high (alpha coefficient is greater than .80). The intra-class correlation (ICC) typically exceeds .80 for a single rater (ICC1) and .90 for the average of two raters (ICC2). The standard error of measurement (SEM) of the PCL-R total score is approximately 3 for a single rating and 2 for the average of two ratings.
The PCL-R also has good generalizability across diverse forensic populations, although there may be sex, ethnic, and cultural differences in the way some features of psychopathy are manifested. Recent research suggests that the construct underlying the PCL-R is dimensional in nature, but a cut score of 30 has proven useful as a working definition of psychopathy. The utility of cut scores for clinical and forensic purposes will be influenced by the context in which the PCL-R is used (e.g., research, diagnosis, risk assessment, treatment options).
Although there is good evidence that the PCL-R measures a unitary construct, the items can be grouped, logically and statistically, into several correlated dimensions or factors. Recent confirmatory factor analyses of very large data sets clearly indicate that a four-factor model (18 items) fits the data well: Interpersonal (Glibness/superficial charm, Grandiose sense of self-worth, Pathological lying, Conning/manipulative); Affective (Lack of remorse or guilt, Shallow affect, Lack of empathy, Failure to accept responsibility for actions); Lifestyle (Need for stimulation/proneness to boredom, Parasitic lifestyle, Lack of realistic long-term goals, Impulsivity, Irresponsibility); and Antisocial (Poor behavioral controls, Early behavior problems, Juvenile delinquency, Revocation of conditional release, Criminal versatility). Two other items (Promiscuous sexual behavior, Many short-term marital relationships) do not load on any factor but contribute to the total PCL-R score. Some commentators have suggested that the Antisocial factor is a measure of criminality and that it is a manifestation of the more central features of psychopathy. In reality, it reflects a pattern of persistent and serious rule-breaking behavior. Clinical tradition, as well as recent findings from behavioral genetics and developmental research, clearly indicates that antisocial dispositions are an integral part of the construct and its measurement.
PCL-R Association with Other Measures
Psychopathy, as measured by the PCL-R, is treated by some as being equivalent with the DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, fourth edition) diagnosis of antisocial personality disorder (APD). However, the diagnostic criteria for APD place greater emphasis on antisocial behaviors than does the PCL-R and are more closely associated with the Lifestyle/Antisocial components of psychopathy than with its Interpersonal/Affective features. Most of those with APD do not have high PCL-R scores (i.e., in the 30+ range). Psychopathy and APD are related but not identical constructs.
The PCL-R is moderately correlated, in expected directions, with various self-report measures of psychopathy and with several omnibus personality scales. These instruments make it easy to collect large amounts of data and are beginning to play a role in delineating and elucidating the nomological network, behavioral genetics, and developmental pathways of psychopathy. They also provide support for the view that psychopathy is an extreme variant of normal personality dimensions.
PCL-R Validity
The validity of the PCL-R in the criminal justice system is well established, a reflection of the central and pervasive role of psychopathy in criminal behavior. There is extensive evidence for the explanatory power and utility of the PCL-R in the prediction of recidivism, violence, and treatment outcome in criminals and in forensic and civil psychiatric populations. The PCL-R routinely is used in risk assessments, either on its own or, more appropriately, as part of a battery of variables and factors relevant to offending and violence. Besides forensic and applied areas, evidence for the validity of the PCL-R is provided by findings obtained from a wide variety of laboratory, cognitive/affective, and neuroscience paradigms, including functional magnetic resonance imaging.
Current Issues
The widespread acceptance of the PCL-R as the principal method for assessing psychopathy and its frequent description as the “gold standard” have led some commentators to express their concern that the measure has become the construct. The remedy is to introduce and validate supplementary or improved assessment methods. A more pressing concern is the potential for misuse of the PCL-R in the forensic context. Because assessments of psychopathy can have serious consequences for the individual and society, it is crucial that the PCL-R (and other instruments) be used in accordance with the highest professional and ethical standards and that such use be subjected to careful scrutiny by the stakeholders.
References:
- Hare, R. D. (2003). The Hare Psychopathy Checklist—Revised (2nd ed.). Toronto, ON, Canada: Multi-Health Systems.
- Hare, R. D. (2007). Psychological instruments in the assessment of psychopathy. In A. R. Felthous & H. Sass (Eds.), International handbook on psychopathic disorders and the law (pp. 41-67). New York: Wiley & Sons.
- Neumann, C. S., Hare, R. D., & Newman, J. (2007). The superordinate nature of the Psychopathy Checklist-Revised. Journal of Personality Disorders, 21, 102-117.
- Leistico, A. R., Salekin, R. T., DeCoster, J., & Rogers, R. (in press). A large-scale meta-analysis relating the Hare measures of psychopathy to antisocial conduct. Law and Human Behavio
- Herve, H., & Yuille, J. (Eds.). (2007). The psychopath: Theory, research, and practice. Mahwah, NJ: Lawrence Erlbaum.