title: Diagnostic stability 2 years after treatment initiation in the early psychosis intervention programme in Singapore.
abstract: OBJECTIVE
  To evaluate the diagnostic stability of psychotic disorders over a 2 year period in patients presenting with first-episode psychosis.
  
  
  METHODS
  One hundred and fifty-four patients were recruited from an early psychosis intervention programme (EPIP). They were diagnosed by the attending psychiatrist using the Structured Clinical Interview for DSM-IV Axis I at first contact (baseline) and after 24 months. The diagnoses were classified into the following categories: schizophrenia spectrum disorders (schizophrenia, schizophreniform disorder and schizoaffective disorder), affective psychosis (bipolar and major depressive disorders with psychotic symptoms), and other non-affective psychosis (delusional disorder, psychosis not otherwise specified and brief psychotic disorder). Two measures of stability, the prospective and the retrospective consistency were determined for each diagnosis.
  
  
  RESULTS
  The diagnoses with the best prospective consistency were schizophrenia (87.0%) and affective psychosis (54.5%). The shift into schizophrenia spectrum disorder was the most frequent diagnostic change. Duration of untreated psychosis was found to be the only significant predictor of shift.
  
  
  CONCLUSIONS
  It is difficult to make a definitive diagnosis at first contact. The clinical need to review the diagnosis throughout the period of follow up is emphasized.
authors.affiliation: Institute of Mental Health, 10 Buangkok View, Singapore.
authors.forename: Mythily
authors.initials: M
authors.lastname: Subramaniam
authors.forename: Elaine
authors.initials: E
authors.lastname: Pek
authors.forename: Swapna
authors.initials: S
authors.lastname: Verma
authors.forename: Yiong Huak
authors.initials: YH
authors.lastname: Chan
authors.forename: Siow Ann
authors.initials: SA
authors.lastname: Chong
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D003937:Diagnosis, Differential; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008605:Mental Health Services / Q000458:organization & administration*; D019964:Mood Disorders / Q000175:diagnosis* / Q000453:epidemiology / Q000534:rehabilitation*; D015588:Observer Variation; D011446:Prospective Studies; D011618:Psychotic Disorders / Q000175:diagnosis* / Q000453:epidemiology / Q000534:rehabilitation*; D012559:Schizophrenia / Q000175:diagnosis* / Q000453:epidemiology / Q000534:rehabilitation*; D012846:Singapore; D013997:Time Factors