title: Wisconsin Card Sorting Test in chronic severe traumatic brain injury: factor structure and performance subgroups.
abstract: OBJECTIVE
  The present study further investigated the factor structure of the WCST in traumatic brain injury and investigated the construct validity and relationships among scores through the use of cluster analysis.
  
  
  METHODS
  Participants were 68 survivors of chronic severe TBI, living at a residential brain injury rehabilitation facility.
  
  
  METHODS
  Three sets of WCST scores were submitted to factor analysis; the regression factor scores based on the standard WCST were examined using cluster analysis.
  
  
  RESULTS
  Factor analysis of the WCST raw scores replicated the three-factor solution which has been previously reported. When t-scores were analysed, two-to-four-factor solutions could be justified. The cluster analysis identified four groups representing: (1) impaired response maintenance; (2) problem-solving deficits; (3) intact WCST performance; and (4) deficits in set shifting.
  
  
  CONCLUSIONS
  The results support previous research indicating that the WCST is sensitive to three distinct cognitive processes: cognitive flexibility, problem-solving, and response maintenance. However, unlike the cognitive processes underlying WCST performance, the WCST scores representing these processes are not independent. The potential clinical relevance of these results is discussed.
authors.affiliation: Department of Psychology, University of New Orleans, New Orleans, LA 70148, USA. kwgps@uno.edu
authors.forename: Kevin W
authors.initials: KW
authors.lastname: Greve
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Love
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Sherwin
authors.forename: Charles W
authors.initials: CW
authors.lastname: Mathias
authors.forename: Paul
authors.initials: P
authors.lastname: Ramzinski
authors.forename: Jose
authors.initials: J
authors.lastname: Levy
mesh_terms: D000293:Adolescent; D000328:Adult; D001930:Brain Injuries / Q000523:psychology*; D002648:Child; D016000:Cluster Analysis; D003071:Cognition; D005163:Factor Analysis, Statistical; D006801:Humans; D009483:Neuropsychological Tests / Q000592:standards*; D011594:Psychometrics; D015203:Reproducibility of Results; D012718:Set, Psychology; D012720:Severity of Illness Index