title: Neuropsychological performance over time in people at high risk of developing schizophrenia and controls.
abstract: BACKGROUND
  Neuropsychological assessments of relatives of schizophrenics have shown subtle impairments in verbal memory, executive and intellectual function, which are stable in those beyond the age of maximum risk for the disorder. We sought to: (1) determine baseline neurocognitive predictors of psychosis, and (2) compare performance over time between relatives within the age of maximum risk, and controls.
  
  
  METHODS
  (1) and (2) were examined in 118 individuals at familial high risk of schizophrenia (HR) and 30 controls (C), using one-way analyses of variance (ANOVAs) and repeated measures analyses of covariance (ANCOVAs), controlling for intelligence quotient, time between and number of assessments, and correcting for multiple comparisons.
  
  
  RESULTS
  HR who became ill (n = 13) performed nonsignificantly less well at baseline than HR who did not (n = 105) on a test of verbal learning (t(109) = 2.1, p = .03). Across assessments, C performed significantly better than the entire HR group on immediate (F(3,133) = 5.11, p = .002) and delayed (F(3,133) = 5.02, p = .002) story recall. There were no significant interactions of time by group.
  
  
  CONCLUSIONS
  Results suggest greater verbal memory impairment in HR who go on to develop schizophrenia. Stable differences between groups over time suggest a trait deficit, which is relatively unaffected by the presence of psychotic symptoms and psychosis onset. Alternatively, small numbers may have precluded detection of group by time interactions.
authors.affiliation: Division of Psychiatry, University of Edinburgh, Morningside Park, Edinburgh, United Kingdom.
authors.forename: Marie-Claire
authors.initials: MC
authors.lastname: Whyte
authors.forename: Caroline
authors.initials: C
authors.lastname: Brett
authors.forename: Lesley K
authors.initials: LK
authors.lastname: Harrison
authors.forename: Majella
authors.initials: M
authors.lastname: Byrne
authors.forename: Patrick
authors.initials: P
authors.lastname: Miller
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Lawrie
authors.forename: Eve C
authors.initials: EC
authors.lastname: Johnstone
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007360:Intelligence / Q000502:physiology; D007361:Intelligence Tests / Q000706:statistics & numerical data; D008297:Male; D008568:Memory / Q000502:physiology; D008609:Mental Status Schedule; D009483:Neuropsychological Tests / Q000706:statistics & numerical data*; D011237:Predictive Value of Tests; D011594:Psychometrics; D012189:Retrospective Studies; D012306:Risk; D012559:Schizophrenia / Q000503:physiopathology*; D012565:Schizophrenic Psychology; D013997:Time Factors; D014706:Verbal Learning / Q000502:physiology