Abstract
Background: In psychometric research examining risk for schizophrenia it is commonplace to label questionnaires as measures of thinking style or personality rather than schizotypy or schizophrenia risk as it is thought that reference to schizophrenia risk may elicit defensive responding. However, defensive responding on schizotypy questionnaires has not been explored in research and there is no evidence that this is the case.
Objective: The aim of this study was to examine whether explicit labelling on schizotypy questionnaires elicits research participants to respond defensively on these measures. It was predicted that participants would obtain lower scores on schizotypy questionnaires when these questionnaires made reference to schizophrenia risk. Secondary objectives of the study were to examine (a) the factors that influence defensive responding, (b) whether differences in defensive responding were observed across positive and negative schizotypy, and (c) whether labelling effects generalise to subsequently administered, benignly labelled questionnaires.
Method: Participants (N = 240) were randomly assigned to one of four conditions and completed differently labelled versions of the SPQ and TPSQ. Questionnaires were labelled with reference to personality or schizophrenia risk. Participants also completed measures assessing stigma, personal experience of mental illness, and a test of schizophrenia knowledge.
Results: Overall, the use of the schizophrenia risk label led to defensive responding on both the SPQ and the TPSQ, with label found to significantly predict scores on the interpersonal deficits factor of the SPQ and the physical and social anhedonia factors of the TPSQ. There was evidence that a generalised bias was created by the schizophrenia risk label, which resulted in lower scores on subsequently administered, benignly labelled questionnaires. No relationship was found between defensive responding and stigma, personal experience of mental illness, or knowledge of schizophrenia.
Conclusion: Non-help seeking undergraduates respond defensively on measures of schizotypy when questionnaires were labelled with reference to schizophrenia risk. The use of the schizophrenia risk label causes defensive responding on these measures.