Psychometric properties and validity of short forms of the Wisconsin Schizotypy Scales in two large samples

The Wisconsin Schizotypy Scales (WSS) have been widely used in the study of clinical and non-clinical samples. However, researchers often find the length of the scales prohibitive. The present study examined the reliability and validity of recently developed 15-item short forms of the Perceptual Aberration, Magical Ideation, Physical Anhedonia, and Revised Social Anhedonia Scales in two large samples of non-clinically ascertained young adults. The scales demonstrated good reliability and correlated highly with the original scales. The validity of the scales was assessed by comparing the association of the original and shortened WSS with interview measures of psychotic-like and schizophrenia-spectrum symptoms and impaired functioning, as well as with questionnaire measures of personality and social impairment. The associations of the shortened WSS with the interview and questionnaire measures were comparable in terms of statistical significance and effect size with the associations of the original scales. The present findings provide the first demonstration of the validity of the shortened WSS and support their use in the study of schizotypy.