Psychopathy across cultures: North America and Scotland compared

Area of Science:

• Forensic Psychology
• Cross-Cultural Psychology
• Psychopathology

Background:

• Psychopathic personality disorder (PPD) prevalence and presentation may vary across cultural contexts.
• Understanding these differences is crucial for accurate diagnosis and effective treatment.

Purpose of the Study:

• To evaluate differences in PPD prevalence and presentation between North American and Scottish male forensic populations.
• To investigate item performance and scale equivalence of the Psychopathy Checklist--Revised (PCL-R) across these two settings.

Main Methods:

• Utilized item response theory (IRT) methods to analyze PCL-R ratings from 2,067 North American and 246 Scottish male prisoners.
• Compared PCL-R item performance and equated the scale across the North American and Scottish samples.

Main Results:

• PCL-R items demonstrated equal relevance in describing PPD in both North America and Scotland.
• Scottish prisoners needed higher levels of the underlying latent trait for specific PPD characteristics to manifest.
• The prevalence of PPD appears lower in Scotland compared to North America.

Conclusions:

• Cultural factors such as enculturation, socialization, and migration may explain observed differences in PPD presentation and prevalence.
• Further research is needed to fully elucidate the impact of these factors on psychopathy.