Validation of Long Forms Schizotypal Personality Questionnaire (SPQ): DSM-IV-TR's Nine Criteria Measure



Introduction: The different scales for assessing Schizotypal traits were developed from different perspectives. These scales confined themselves only to certain aspects of the Schizotypal personality. In contrast, the Schizotypal Personality Questionnaire is more comprehensive scale based on nine clinical features of Schizotypal personality disorder described by the DSM-IV-TR. The aim of this study was validation and factor analysis of the Schizotypal Personality Questionnaire (SPQ).
Method: The current study was conducted in descriptive research context. A group of 609 normal participants (187 male  422 female) from Tabriz Payame Nour and Azad University and Sarab Payame Nour University students took part in this research.
Results: Two and three factor solutions were investigated using Principal Component Analysis with Promax rotation, but two factor solutions showed better logical and symptomological fitnesses. There are no sex differences in Schizotypy among groups. To calculate the convergent validity of SPQ and its negative & positive factors, concurrent application of Schizotypal Trait Questionnaire A form was used and was found to have 0.80, 0.75, 0.82 correlations. The SPQ and its negative & positive factors were found to have 0.74, 0.77, 0.83 internal reliability, 0.80, 0.72, 0.70 test-retest reliability.
Conclusion: Based on these results, it was concluded that SPQ contain good validity and reliability in Iranian population and it can be used, as valid measure, in Psychological and Psychiatric researches.