Self-reported psychopathic traits among non-referred Finnish adolescents: psychometric properties of the Youth Psychopathic traits Inventory and the Antisocial Process Screening Device.

Background: In general psychiatric services, cost-benefit screening instruments for psychopathic traits in adolescents are needed. The aim of the present study was to study the psychometric properties of the Finnish versions of the Youth Psychopathic traits Inventory (YPI) and the Antisocial Process Screening Device (APSD-SR) in community youth. As gender-specific differences exist in psychopathic traits, we analyzed the data separately in girls and boys.

Methods: The YPI and the APSD-SR were administered to 372 9th graders (174 boys and 198 girls) with a mean age of 15.06 years (SD 0.28). Cronbach's alphas were used to study internal consistency. The factor structures of the self-assessments were studied using both Confirmatory Factor Analysis (CFA) and Principal Component Analysis (PCA).

Results: In both self-assessments, boys scored significantly higher in the total scores, Interpersonal and Affective dimension scores as well as in most sub-dimensions. In the YPI, the alpha values for total and dimensional scores ranged from 0.55 to 0.91 in boys and from 0.74 to 0.89 in girls and, in the APSD-SR, respectively, from 0.38 to 0.78 and from 0.29 to 0.78. In CFA, the three-factor model produced poor fit for both self-assessments. For the ten sub-dimensions of the YPI, the PCA suggested two factors. Extending the model into three components showed sub-dimension loadings according to the original dimensions. For the APSD-SR, the PCA revealed a five-factor structure in the male sample and a six-factor one in the female group. When limiting the model to a three factor- model, we obtained a structure, which resembled the original dimensions.

Conclusions: Both the YPI and the APSD-SR are promising tools of screening for psychopathic features in Finnish community youth. The YPI turned out to be slightly better than the APSD- SR in both reliability and factor structure. However, the original three-factor models did not find support. Both self-assessments were somewhat weak for tapping the callous-unemotional traits of the psychopathic character, but, again, the YPI worked better than the ASPD-SR. Both self-assessments revealed significant gender differences in psychopathic character traits.