Van Os et al. (2009) have proposed a Proneness-Persistence-lmpairment model to explain the psychosis continuum, and cognitive models of psychosis have suggested that appraisals of anomalous experiences may be key in determining ‘need for care’.

The present study investigated the interaction between appraisals and safety behaviours in the maintenance of impairing psychotic symptoms.

It was predicted that individuals with psychotic symptoms without a need for care would display fewer threat appraisals and safety behaviours than their clinical counterparts, and that these variables would predict distress.

The study recruited people with persistent psychotic experiences but who had no-need-for-care (Persistence group; n = 39) and individuals diagnosed with a psychotic disorder who were receiving current treatment (Impairment group; n = 28). The participants were assessed on semi-structured interviews of appraisals and safety behaviours in relation to their psychotic experiences and on anxiety and depression questionnaires.

Both groups had similar levels of psychotic symptoms in the last month, including first rank symptoms. However there was a large significant difference between Impairment and Persistence groups in threat appraisals and safety behaviours, with the Persistence group reporting higher levels of both. A mediation analysis found that threat appraisals mediated the relationship between safety behaviours and anomaly-related distress, suggesting that threat appraisals may maintain anomaly-related distress, a defining feature of Impairment status.

These data provide support for the cognitive model of psychosis, with threat appraisals potentially playing a major role in the transition from non-clinical anomalous experiences to clinical psychotic status.