Outreach and Support in South London (OASIS). Outcomes of non-attenders to a service for people at high risk of psychosis: the case for a more assertive approach to assessment.

BACKGROUND: International agreement dictates that clients must be help-seeking before any assessment or intervention can be implemented by an 'at-risk service'. Little is known about individuals who decline input. This study aimed to define the size of the unengaged population of an 'at-risk service', to compare this group to those who did engage in terms of sociodemographic and clinical features and to assess the clinical outcomes of those who did not engage with the service. METHOD: Groups were compared using data collected routinely as part of the service's clinical protocol. Data on service use and psychopathology since referral to Outreach and Support in South London (OASIS) were collected indirectly from clients' general practitioners (GPs) and by screening electronic patient notes held by the local Mental Health Trust. RESULTS: Over one-fifth (n=91, 21.2%) of those referred did not attend or engage with the service. Approximately half of this group subsequently received a diagnosis of mental illness. A diagnosis of psychosis was given to 22.6%. Nearly 70% presented to other mental health services. There were no demographic differences, except that those who engaged with the service were more likely to be employed. CONCLUSIONS: Over one-fifth of those referred to services for people at high risk of psychosis do not attend or engage. However, many of this group require mental health care, and a substantial proportion has, or will later develop, psychosis. A more assertive approach to assessing individuals who are at high risk of psychosis but fail to engage may be indicated.

Measuring ideas of persecution and social reference: the Green et al. Paranoid Thought Scales (GPTS).

BACKGROUND: Paranoia is increasingly being studied in clinical and non-clinical populations. However there is no multi-dimensional measure of persecutory ideas developed for use across the general population-psychopathology continuum. This paper reports the development of such a questionnaire: the 'Green et al. Paranoid Thought Scales'. The aim was to devise a tool to assess ideas of persecution and social reference in a simple self-report format, guided by a current definition of persecutory ideation, and incorporating assessment of conviction, preoccupation and distress. METHOD: A total of 353 individuals without a history of mental illness, and 50 individuals with current persecutory delusions completed a pool of paranoid items and additional measures to assess validity. Items were devised from a recent definition of persecutory delusions, current assessments of paranoia, the authors' clinical experience, and incorporated dimensions of conviction, preoccupation and distress. Test-retest reliability in the non-clinical group was assessed at 2 weeks follow-up, and clinical change in the deluded group at 6 months follow-up. RESULTS: Two 16-item scales were extracted, assessing ideas of social reference and persecution. Good internal consistency and validity was established for both scales and their dimensions. The scales were sensitive to clinical change. A hierarchical relationship between social reference and persecution was found. The data provide further evidence for a continuum of paranoid ideas between deluded and healthy individuals. CONCLUSIONS: A reliable and valid tool for assessing paranoid thoughts is presented. It will provide an effective way for researchers to ensure consistency in research and for clinicians to assess change with treatment.