Personality disorder in university students: a multitrait-multimethod matrix study.

Area of Science:

• Psychology
• Clinical Psychology
• Psychopathology

Background:

• Personality disorders (PDs) represent enduring patterns of inner experience and behavior that deviate markedly from the expectations of an individual's culture.
• Assessing PD prevalence in student populations is crucial for understanding mental health needs in young adults.
• Previous research indicates a general prevalence range of 5% to 15% in non-clinical samples.

Purpose of the Study:

• To examine the prevalence of personality disorders in a sample of first-year university students.
• To compare the prevalence estimates derived from three distinct self-report measures.
• To investigate the interrelationships and construct overlap among various personality disorders.

Main Methods:

• Utilized three self-report instruments: Coolidge Axis II Inventory (CATI), Millon Clinical Multiaxial Inventory-II (MCMI-II), and Minnesota Multiphasic Personality Inventory-Personality Disorder Scale (MMPI-PD).
• Prevalence was determined by the number of participants exceeding established cut-off scores for each PD instrument.
• A multitrait-multimethod matrix was employed to assess correlations between disorders across the different measures.

Main Results:

• Estimated PD prevalence ranged from 0% to 16% for males and 1% to 26% for females, aligning with established ranges for non-patient samples.
• The three assessment tools demonstrated general consistency in estimating the prevalence of the 11 personality disorders.
• Significant positive correlations were observed between most PDs across all measures, indicating substantial construct overlap.
• Passive-aggressive and schizotypal disorders showed the most convergent correlations, while schizoid disorder was more discriminant on the MMPI-PD.

Conclusions:

• The study confirms the prevalence rates of personality disorders in a university student population.
• Findings highlight considerable overlap among personality disorders, suggesting shared underlying etiological factors or diagnostic ambiguity.
• The consistency across different measures supports their utility in assessing PDs, while also pointing to the need for careful interpretation due to construct overlap.