Examining the Schizophrenia-Spectrum Specificity of Measures of Schizotypy

Self-report measures of schizotypy are an important tool for identifying individuals who may be considered at higher risk for developing a schizophrenia-spectrum disorder. Previous research into the specificity of such measures has led to mixed results, such that it is unclear whether individuals who are not at higher risk of psychosis are being incorrectly identified as at-risk based on these measures. Using latent profile analysis (LPA), the current study aimed to analyze what overlap may exist in the response patterns of individuals with schizophrenia symptoms, non-schizophrenia-spectrum disorder symptoms, and non-symptomatic individuals using four common self-report measures of schizotypy. The sample (N = 676) was divided into five groups based on participants' endorsement of symptoms of the following disorders: schizophrenia, autism spectrum disorder, depression, or obsessive-compulsive disorder. Another subset of respondents endorsed no symptoms of clinical severity. The optimal LPA model included four latent profiles: high schizotypy, high negative schizotypy, moderate schizotypy, and low schizotypy. In the high schizotypy profile, there was significant overlap among individuals from the schizophrenia symptom group and the obsessive-compulsive disorder symptom group. This suggests that individuals who are not at risk for developing a schizophrenia-spectrum disorder respond to these measures in a similar way to individuals who already exhibit symptoms of such disorders. Another possible explanation for the results is that schizotypy is more of a transdiagnostic construct than previously believed. Continued research is needed to understand the limitations of the individual measures of schizotypy included in this study and determine which explanation is most appropriate. General Scientific SummaryMultiple self-report questionnaires assess schizotypy, which is a set of characteristics that indicate risk of developing schizophrenia-spectrum disorders. This study suggests that some individuals who are not at risk of developing these disorders respond to such questionnaires similarly to individuals who are at risk, which limits the conclusions that can be drawn in research using those questionnaires.