Psychometric Properties of the Externalizing Spectrum Inventory: Replication and Extension across Clinical and Non-Clinical Samples.

The Externalizing Spectrum Inventory aims at assessing personality features that underlie externalizing disorders such as substance abuse and antisocial behaviors. The objective was to replicate the psychometric properties of the 160-item Externalizing Spectrum Inventory in Dutch clinical and non-clinical samples. First, Cronbach's alpha, test-retest reliability and the factor structure were analyzed on a mixed sample of inpatients (n = 149), undergraduates (n = 227), and community participants (n = 178). The factor structure was evaluated through confirmatory and exploratory factor analyses; for the latter Parallel Analysis was used, based on Minimum Rank Factor Analysis. Next, the criterion validity was analyzed using the Aggression Questionnaire and the NEO-Five Factor Inventory as external measures. The Dutch Externalizing Spectrum Inventory subscales showed sufficient reliability (α=.68-.94; ICC=.68-.91), except in the undergraduate sample (α=.49-.96; ICC=.43-.97). The factor structure of the Externalizing Spectrum Inventory was not confirmed and the exploratory analysis yielded different factor solutions across samples. The criterion validity was supported with regard to trait aggression and partly supported with regard to the Five Factor Model. The results suggest that the ESI-160 and its original factor model can be used for prediction purposes. However, further research of the factor structure is strongly recommended.

Further Evidence for Reliability and Validity of the Triarchic Psychopathy Measure in a Forensic Sample and a Community Sample.

Psychopathy is often described as a constellation of personality characteristics encompassing features such as impulsivity and antisociality, and a lack of empathy and guilt. Although the use of self-reports to assess psychopathy is still debated, there are distinct advantages to such measures and recent research suggests that they may not be as problematic as previously thought. This study further examined the reliability and validity of the Triarchic Psychopathy Measure (TriPM) in a community sample (N = 496) and forensic psychiatric patient sample (N = 217). Results indicated excellent internal consistencies. Additionally, the TriPM total and subscale scores related as expected to different subscales of the Psychopathic Personality Inventory -Revised (PPI-R) and to the Reactive and Proactive Aggression Questionnaire, reflecting good construct validity. Most importantly, ROC curve analyses showed that the TriPM evidenced better discrimination between the community sample and forensic psychiatric patients than the PPI-R. The current study extends the existent evidence demonstrating that the TriPM can be used as an efficient self-report instrument.