title: Early-onset schizophrenia in children with mental retardation: diagnostic reliability and stability of clinical features.
abstract: OBJECTIVE
  To investigate the presentation of early-onset schizophrenia in children with mental retardation (MR) and the stability of clinical features over time.
  
  
  METHODS
  A purpose-designed assessment protocol was developed based on best-practice recommendations in the research literature. Diagnostic reliability, investigated in a group of 20 children with MR, was found to be very good (kappa = 0.87). Using this protocol, the clinical service identified 10 children with an initial diagnosis of schizophrenia. This group was then reassessed 2 years later.
  
  
  RESULTS
  At the end of 2 years, 8 of the 10 children with schizophrenia still warranted this diagnosis. However, there was considerable instability in relation to certain diagnostic criteria, notably delusions and visual hallucinations. In all cases some improvements in severity were seen at follow-up. However, the eight whose schizophrenia was confirmed at follow-up showed major deterioration in cognitive level.
  
  
  CONCLUSIONS
  It is possible to make reliable diagnoses of early-onset schizophrenia in people with MR, provided the assessment system is carefully structured and pays attention to all the important sources of information. However, symptoms should be reviewed frequently, particularly those that cannot be substantiated by patient interview.
authors.affiliation: Cheshire and Wirral Partnership NHS Trust, United Kingdom. Pauline.Lee@echeshire-tr.nwest.nhs.uk
authors.forename: Pauline
authors.initials: P
authors.lastname: Lee
authors.forename: Steve
authors.initials: S
authors.lastname: Moss
authors.forename: Robin
authors.initials: R
authors.lastname: Friedlander
authors.forename: Tina
authors.initials: T
authors.lastname: Donnelly
authors.forename: William
authors.initials: W
authors.lastname: Honer
mesh_terms: D000293:Adolescent; D000367:Age Factors; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008607:Intellectual Disability / Q000150:complications*; D008297:Male; D011569:Psychiatric Status Rating Scales; D015203:Reproducibility of Results; D012559:Schizophrenia / Q000150:complications* / Q000175:diagnosis*; D012720:Severity of Illness Index