The creation and validation of the Jamaica Personality Disorder Inventory

Area of Science:

• Psychiatry
• Psychometrics
• Clinical Psychology

Background:

• Personality disorders present a significant challenge in clinical diagnosis.
• Existing screening tools may have limitations in specific populations.
• The phenomenological triad (power management, dependency, psychosexual issues) offers a framework for understanding personality pathology.

Purpose of the Study:

• To develop and validate the Jamaica Personality Disorder Inventory (JPDI) as a screening questionnaire.
• To assess the reliability and validity of the JPDI in a clinical setting.

Main Methods:

• The JPDI, comprising 38 yes/no questions, was developed based on the phenomenological triad.
• Validation involved 200 patients, comparing JPDI results with the International Personality Disorder Examination-Screening Instrument (IPDE-S), Brief Screen for Depression, and DSM-IV diagnoses.
• Statistical analyses included factor analysis, Spearman correlation, Cronbach's alpha, and the Multitrait Multimethod Matrix (MTMM).

Main Results:

• Factor analysis identified eight clusters congruent with the clinical triad.
• The JPDI demonstrated high reliability (Cronbach's alpha = 0.79) and excellent sensitivity (95.06%) with good specificity (67.71%).
• Significant correlations supported the JPDI's concurrent validity with IPDE-S and DSM-IV diagnoses, and predictive validity.

Conclusions:

• The Jamaica Personality Disorder Inventory (JPDI) is a reliable and valid screening tool.
• The JPDI effectively screens for personality disorders, showing strong criterion-related and discriminant validity.
• The findings support the JPDI's utility in clinical practice for personality disorder assessment.