title: First-episode schizophrenia, bipolar disorder and other psychoses in a rural Irish catchment area: incidence and gender in the Cavan-Monaghan study at 5 years.
abstract: BACKGROUND
  The potential of first-episode studies in schizophrenia is maximised through systematic epidemiological, clinical and biological comparisons between homogeneous populations of the psychoses.
  
  
  OBJECTIVE
  To conduct prolonged accrual of 'all' cases of non-affective and affective psychotic illness on an epidemiologically complete basis.
  
  
  METHODS
  Within the region covered by Cavan-Monaghan psychiatric service (population 102,810), all putative cases of first-episode psychosis were diagnosed using DSM-IV.
  
  
  RESULTS
  From 1995 to 2000, 69 cases of psychosis were ascertained, the incidence being 2.3-fold lower in females than in males. On resolving the 'core' diagnoses of schizophrenia and bipolar disorder, incidence of schizophrenia among women was 7.5-fold lower than among men whereas incidence of bipolar disorder among women was 6.6-fold lower than among men.
  
  
  CONCLUSIONS
  This homogeneous population, which eliminates factors associated with urbanicity and minimises confounding factors such as socioeconomic, ethnic and geographical diversity, shows a markedly reduced incidence among females both of schizophrenia and of bipolar disorder.
authors.affiliation: Stanley Research Unit, St Davnet's Hospital, Monaghan, Ireland.
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Scully
authors.forename: John F
authors.initials: JF
authors.lastname: Quinn
authors.forename: Maria G
authors.initials: MG
authors.lastname: Morgan
authors.forename: Anthony
authors.initials: A
authors.lastname: Kinsella
authors.forename: Eadbhard
authors.initials: E
authors.lastname: O'Callaghan
authors.forename: John M
authors.initials: JM
authors.lastname: Owens
authors.forename: John L
authors.initials: JL
authors.lastname: Waddington
mesh_terms: D000704:Analysis of Variance; D001714:Bipolar Disorder / Q000175:diagnosis / Q000453:epidemiology; D002391:Catchment Area, Health; D005260:Female; D006801:Humans; D015994:Incidence; D007494:Ireland / Q000453:epidemiology; D008297:Male; D008605:Mental Health Services / Q000458:organization & administration; D011446:Prospective Studies; D011618:Psychotic Disorders / Q000175:diagnosis / Q000453:epidemiology*; D012423:Rural Health / Q000706:statistics & numerical data; D012559:Schizophrenia / Q000175:diagnosis / Q000453:epidemiology*; D012737:Sex Factors