title: Mixed-handedness in patients with functional psychosis.
abstract: BACKGROUND
  An excess of non-right-handedness has been shown among patients with schizophrenia. However it is not clear whether this finding can be accounted for by an increase in left-handedness, mixed-handedness or both. It is not known whether atypical patterns of hand preferences occur in other functional psychotic illnesses.
  
  
  METHODS
  The Annett hand preference questionnaire was administered to patients with schizophrenia (n = 120); affective psychosis (n = 55); schizoaffective psychosis (n = 41), and control subjects (n = 86). Handedness was classified into three categories: right, mixed and left-handedness.
  
  
  RESULTS
  The hand preference patterns of patients with functional psychotic illnesses were not significantly different from controls. Patients with schizophrenia showed a non-significant excess of mixed-handedness compared with controls. Patients with schizophrenia and affective psychosis showed a non-significant decrease in left-handedness compared with controls.
  
  
  CONCLUSIONS
  Although our results showed a trend in the hypothesised direction, we failed to demonstrate that patients with psychotic illness differed from controls on self-reported hand preference patterns.
authors.affiliation: Department of Psychological Medicine, Institute of Psychiatry, London.
authors.forename: R R
authors.initials: RR
authors.lastname: Malesu
authors.forename: M
authors.initials: M
authors.lastname: Cannon
authors.forename: P B
authors.initials: PB
authors.lastname: Jones
authors.forename: K
authors.initials: K
authors.lastname: McKenzie
authors.forename: K
authors.initials: K
authors.lastname: Gilvarry
authors.forename: L
authors.initials: L
authors.lastname: Rifkin
authors.forename: B K
authors.initials: BK
authors.lastname: Toone
authors.forename: R M
authors.initials: RM
authors.lastname: Murray
mesh_terms: D000328:Adult; D000341:Affective Disorders, Psychotic / Q000175:diagnosis / Q000523:psychology; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008297:Male; D011618:Psychotic Disorders / Q000175:diagnosis* / Q000523:psychology; D012016:Reference Values; D012559:Schizophrenia / Q000175:diagnosis*; D012565:Schizophrenic Psychology