Effects of positive impression management on the Psychopathic Personality Inventory

Area of Science:

• Psychology
• Forensic Psychology
• Clinical Psychology

Background:

• The Psychopathic Personality Inventory (PPI) is a valuable self-report screening tool for psychopathy.
• A significant limitation of the PPI is the lack of research on the impact of response sets, such as positive impression management.
• The PPI includes the Unlikely Virtues validity scale to detect response biases like "faking good," but its effectiveness is unassessed.

Purpose of the Study:

• To investigate the impact of positive impression management (faking good) on Psychopathic Personality Inventory (PPI) scores.
• To evaluate the utility of the PPI's Unlikely Virtues validity scale in detecting "faking good" response sets.

Main Methods:

• A repeated measures analogue design was used with 186 participants.
• Participants completed the PPI under standard conditions and again with instructions to create a favorable impression ("fake good" condition).
• Receiver Operating Characteristic (ROC) analyses were performed to assess the Unlikely Virtues scale's performance.

Main Results:

• Participants in the "fake good" condition scored significantly lower on the PPI, appearing less psychopathic.
• Individuals with higher standard PPI scores showed the greatest reduction in scores when attempting to "fake good."
• The Unlikely Virtues scale differentiated "fake good" from honest protocols (AUC = .73) but resulted in notable misclassifications.

Conclusions:

• The PPI is susceptible to "faking good" attempts, potentially compromising its validity in certain contexts.
• The Unlikely Virtues scale offers some protection against "faking good" but is not infallible.
• Findings have significant clinical and forensic implications for the interpretation of PPI results.