title: Effect of social class at birth on risk and presentation of schizophrenia: case-control study.
abstract: OBJECTIVE
  To examine if low parental social class increases children's risk of subsequently developing schizophrenia or modifies the presentation.
  
  
  METHODS
  Case-control study with historical controls.
  
  
  METHODS
  Geographically defined region in south Dublin.
  
  
  METHODS
  352 patients with first presentation of schizophrenia matched with the next registered same sex birth from the same birth registration district.
  
  
  METHODS
  Social class at birth. Age at presentation to psychiatric services, admission to hospital, and diagnosis of schizophrenia.
  
  
  RESULTS
  Risk of schizophrenia was not increased in people from lower social classes. There was a slight excess risk among people in highest social classes (odds ratio 0.59, 95% confidence interval 0.40 to 0.85). However, the mean age at presentation was 24.8 years for patients whose parents were in the highest social class compared with 33.1 years for those in the lowest social class at birth.
  
  
  CONCLUSIONS
  Although social class of origin does not seem to be an important risk factor for schizophrenia, it partially determines the age at which patients receive treatment. The relation between low social class at birth and poor outcome may be at least partially mediated through treatment delay.
authors.affiliation: Stanley Foundation Research Unit, Department of Adult Psychiatry, Hospitalier Order of St. John of God, Cluain Mhuire Family Centre, Blackrock, Co Dublin, Ireland.
authors.forename: F
authors.initials: F
authors.lastname: Mulvany
authors.forename: E
authors.initials: E
authors.lastname: O'Callaghan
authors.forename: N
authors.initials: N
authors.lastname: Takei
authors.forename: M
authors.initials: M
authors.lastname: Byrne
authors.forename: P
authors.initials: P
authors.lastname: Fearon
authors.forename: C
authors.initials: C
authors.lastname: Larkin
mesh_terms: D000328:Adult; D000367:Age Factors; D017668:Age of Onset; D016022:Case-Control Studies; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D007231:Infant, Newborn; D007494:Ireland; D008297:Male; D016017:Odds Ratio; D010342:Patient Acceptance of Health Care / Q000706:statistics & numerical data; D012307:Risk Factors; D012559:Schizophrenia / Q000209:etiology*; D012923:Social Class