title: Predicting psychosis: meta-analysis of transition outcomes in individuals at high clinical risk.
abstract: BACKGROUND
  A substantial proportion of people at clinical high risk of psychosis will develop a psychotic disorder over time. However, the risk of transition to psychosis varies between centers, and some recent work suggests that the risk of transition may be declining.
  
  
  OBJECTIVE
  To quantitatively examine the literature to date reporting the transition risk to psychosis in subjects at clinical high risk.
  
  
  METHODS
  The electronic databases were searched until January 2011. All studies reporting transition risks in patients at clinical high risk were retrieved.
  
  
  METHODS
  Twenty-seven studies met the inclusion criteria, comprising a total of 2502 patients.
  
  
  METHODS
  Transition risks, as well as demographic, clinical, and methodologic variables, were extracted from each publication or obtained directly from its authors.
  
  
  RESULTS
  There was a consistent transition risk, independent of the psychometric instruments used, of 18% after 6 months of follow-up, 22% after 1 year, 29% after 2 years, and 36% after 3 years. Significant moderators accounting for heterogeneity across studies and influencing the transition risks were the age of participants, publication year, treatments received, and diagnostic criteria used. There was no publication bias, and a sensitivity analysis confirmed the robustness of the core findings.
  
  
  CONCLUSIONS
  The state of clinical high risk is associated with a very high risk of developing psychosis within the first 3 years of clinical presentation, and the risk progressively increases across this period. The transition risk varies with the age of the patient, the nature of the treatment provided, and the way the syndrome and transition to psychosis are defined.
authors.affiliation: Department of Psychosis Studies, Institute of Psychiatry, King's College London, London, United Kingdom. p.fusar@libero.it
authors.forename: Paolo
authors.initials: P
authors.lastname: Fusar-Poli
authors.forename: Ilaria
authors.initials: I
authors.lastname: Bonoldi
authors.forename: Alison R
authors.initials: AR
authors.lastname: Yung
authors.forename: Stefan
authors.initials: S
authors.lastname: Borgwardt
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Kempton
authors.forename: Lucia
authors.initials: L
authors.lastname: Valmaggia
authors.forename: Francesco
authors.initials: F
authors.lastname: Barale
authors.forename: Edgardo
authors.initials: E
authors.lastname: Caverzasi
authors.forename: Philip
authors.initials: P
authors.lastname: McGuire
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D018450:Disease Progression; D006801:Humans; D053208:Kaplan-Meier Estimate; D011569:Psychiatric Status Rating Scales; D011618:Psychotic Disorders / Q000175:diagnosis* / Q000209:etiology / Q000523:psychology; D012307:Risk Factors; D055815:Young Adult