The debate over whether, and how, proneness to schizophrenia can be detected before a psychotic incident occurs has run for a number of decades. Theories of psychosis proneness, known as schizotypy, began to emerge in the 1950s. At this time the focus of attention was on people who were biologically related to a person diagnosed with schizophrenia, yet not themselves psychotic.
Today's classification system (DSM-IV-TR and ICD-10) refers to schizotypal personality disorder. In fact two...

