The Kings Schizotypy Questionnaire as a quantitative measure of schizophrenia liability

Jones, L.A.; Cardno, A.G.; Murphy, K.C.; Sanders, R.D.; Gray, M.Y.; McCarthy, G.; McGuffin, P.; Owen, M.J.; Williams, J.

« Previous Next »Schizophrenia Research
Volume 45, Issue 3 , Pages 213-221, 27 October 2000

The Kings Schizotypy Questionnaire as a quantitative measure of schizophrenia liability

L.A. Jones
- Division of Psychological Medicine, University of Wales College of Medicine, Heath Park, Cardiff CF14 4XN, UK
- Corresponding author. Tel: +44-29-20-744284/743247; fax: +44-29-20-747839
A.G. Cardno
- Division of Psychological Medicine, University of Wales College of Medicine, Heath Park, Cardiff CF14 4XN, UK
K.C. Murphy
- Division of Psychological Medicine, University of Wales College of Medicine, Heath Park, Cardiff CF14 4XN, UK
R.D. Sanders
- Division of Psychological Medicine, University of Wales College of Medicine, Heath Park, Cardiff CF14 4XN, UK
M.Y. Gray
- Division of Psychological Medicine, University of Wales College of Medicine, Heath Park, Cardiff CF14 4XN, UK
G. McCarthy
- Division of Psychological Medicine, University of Wales College of Medicine, Heath Park, Cardiff CF14 4XN, UK
P. McGuffin
- Division of Psychological Medicine, University of Wales College of Medicine, Heath Park, Cardiff CF14 4XN, UK
- Division of Medical Genetics, University of Wales College of Medicine, Heath Park, Cardiff CF14 4XN, UK
M.J. Owen
- Division of Psychological Medicine, University of Wales College of Medicine, Heath Park, Cardiff CF14 4XN, UK
- Division of Medical Genetics, University of Wales College of Medicine, Heath Park, Cardiff CF14 4XN, UK
J. Williams
- Division of Psychological Medicine, University of Wales College of Medicine, Heath Park, Cardiff CF14 4XN, UK

Received 10 September 1999; accepted 10 September 1999.

Abstract

We used a new self-report measure, the Kings Schizotypy Questionnaire (KSQ; Williams, M. The psychometric assessment of schizotypal personality. PhD thesis. Institute of Psychiatry, University of London, 1993), to investigate schizotypy as a quantitative measure of familial liability to schizophrenia. The KSQ was administered to 135 DSM-IV schizophrenia probands, 153 of their healthy first-degree relatives, and 267 control subjects. We found that the questionnaire clearly differentiated schizophrenic from non-schizophrenic individuals, but failed to differentiate the relatives from controls. Possible reasons for this include defensive responding among relatives, self-selection bias among relatives, differences in data collection methods, and the possibility that positive aspects of schizotypy may not be closely related to familial liability to schizophrenia.

Keywords: Kings Schizotypy Questionnaire, Schizophrenia liability, Schizotypy