title: Are there sub-types of attentional deficits in patients with persisting post-concussive symptoms? A cluster analytical study.
abstract: OBJECTIVE
  The present study aimed to examine attentional deficits in patients with persisting post-concussive symptoms using a multi-componential framework of attention.
  
  
  METHODS
  A cross-sectional investigation using standardized tests and questionnaires of attention including 92 patients.
  
  
  METHODS
  Participants were administered comprehensive measures of attention assessing sustained attention (Sustained Attention Response to Task, Backward Digit Span), selective attention (Stroop Word-Colour Test, Colour Trails Test), divided attention (Paced Auditory Serial Addition Test, Symbol Digit Modalities Test), and attentional control (Tower of Hanoi, Six Elements Test). Ecological tests of attention were used to validate the cluster solution.
  
  
  RESULTS
  Three clusters of patients with different combinations of attentional deficits were identified. They were 'mild sustained attentional deficits', 'selective and divided attentional deficits', and 'general attentional deficit'. A MANOVA indicated that these three clusters were statistically and clinically different from one another in terms of different attentional components proposed.
  
  
  CONCLUSIONS
  This study provides preliminary evidence suggesting that sub-types of attentional impairments exit in patients with post-concussive symptoms.
authors.affiliation: Department of Psychiatry, the University of Hong Kong, Hong Kong, PR China. rckchan@hkucc.hku.hk
authors.forename: Raymond C K
authors.initials: RC
authors.lastname: Chan
authors.forename: Rumjahn
authors.initials: R
authors.lastname: Hoosain
authors.forename: Tatia M C
authors.initials: TM
authors.lastname: Lee
authors.forename: Y W
authors.initials: YW
authors.lastname: Fan
authors.forename: Dawson
authors.initials: D
authors.lastname: Fong
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001289:Attention Deficit Disorder with Hyperactivity / Q000523:psychology*; D016000:Cluster Analysis; D003072:Cognition Disorders / Q000145:classification* / Q000209:etiology / Q000523:psychology; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D038223:Post-Concussion Syndrome / Q000150:complications / Q000523:psychology*; D011581:Psychological Tests