A diagnostic classification version of Schizotypal Personality Questionnaire using diagnostic classification models

Area of Science:

• Psychometrics
• Clinical Psychology
• Psychiatry

Background:

• Schizotypal personality disorder (SPD) assessment traditionally relies on questionnaires with limitations in precision.
• Diagnostic Classification Models (DCMs) offer a more advanced psychometric framework for diagnostic assessment.

Purpose of the Study:

• To develop a diagnostic classification version of the Schizotypal Personality Questionnaire (DC-SPQ) aligned with DSM-5 criteria.
• To leverage DCMs for enhanced precision and richness in SPD measurement.

Main Methods:

• Recruited 980 college students for item parameter calibration of the Schizotypal Personality Questionnaire under DCMs.
• Selected items with appropriate psychometric characteristics to form the DC-SPQ.
• Analyzed the reliability, validity, and diagnostic accuracy of the DC-SPQ.

Main Results:

• The DC-SPQ demonstrated high reliability and validity under both classical test theory and DCMs.
• Achieved a sensitivity of 0.921, specificity of 0.841, and an AUC of 0.936.
• The four-factor model showed adequate data fit, and the DC-SPQ provided both general and symptom-level information.

Conclusions:

• The DC-SPQ is a valuable tool for psychometric detection of schizotypal personality disorder.
• It clarifies measured symptoms and provides more accurate estimates, enabling individualized interventions.