title: Response-time variability is related to parent ratings of inattention, hyperactivity, and executive function.
abstract: OBJECTIVE
  Individuals with ADHD are often characterized as inconsistent across many contexts. ADHD is also associated with deficits in executive function. We examined the relationships between response time (RT) variability on five brief computer tasks to parents' ratings of ADHD-related features and executive function in a group of children with a broad range of ADHD symptoms from none to full diagnosis.
  
  
  METHODS
  We tested 98 children (mean age 9.9 ± 1.4 years; 66 boys) from community clinics on short tasks of executive control (TEC) and the Eriksen Flanker task, while a parent completed the Conners' Parent Rating Scale and Behavior Rating Inventory of Executive Function.
  
  
  RESULTS
  Variability for two of the TEC tasks explained significant proportions of the variance of all five ADHD-related Conners' subscales and several executive function subscales. By contrast, variability on the flanker task or mean RTs for any task were not associated with any rating scale.
  
  
  CONCLUSIONS
  The significant dimensional relationships observed between variability measures and parent ratings supported the utility of RT variability as an objective measure in ADHD and aspects of executive functioning that is superior to RT means or accuracy measures.
authors.affiliation: Servicio de Psiquiatría, Hospital Provincial de Pontevedra, Santiago de Compostela (La Coruña), Spain.
authors.forename: Lorena
authors.initials: L
authors.lastname: Gómez-Guerrero
authors.forename: Cristina Domínguez
authors.initials: CD
authors.lastname: Martín
authors.forename: María Angeles
authors.initials: MA
authors.lastname: Mairena
authors.forename: Adriana
authors.initials: A
authors.lastname: Di Martino
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.forename: Alan L
authors.initials: AL
authors.lastname: Mendelsohn
authors.forename: Benard P
authors.initials: BP
authors.lastname: Dreyer
authors.forename: Peter K
authors.initials: PK
authors.lastname: Isquith
authors.forename: Gerard
authors.initials: G
authors.lastname: Gioia
authors.forename: Eva
authors.initials: E
authors.lastname: Petkova
authors.forename: F Xavier
authors.initials: FX
authors.lastname: Castellanos
mesh_terms: D001288:Attention; D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis* / Q000523:psychology; D002648:Child; D056344:Executive Function; D005260:Female; D006801:Humans; D006948:Hyperkinesis / Q000175:diagnosis* / Q000523:psychology; D008297:Male; D009483:Neuropsychological Tests; D010290:Parents; D010865:Pilot Projects; D011930:Reaction Time