title: Cognitive training for attention-deficit/hyperactivity disorder: meta-analysis of clinical and neuropsychological outcomes from randomized controlled trials.
abstract: OBJECTIVE
  The authors performed meta-analyses of randomized controlled trials to examine the effects of cognitive training on attention-deficit/hyperactivity disorder (ADHD) symptoms, neuropsychological deficits, and academic skills in children/adolescents with ADHD.
  
  
  METHODS
  The authors searched Pubmed, Ovid, Web of Science, ERIC, and CINAHAL databases through May 18, 2014. Data were aggregated using random-effects models. Studies were evaluated with the Cochrane risk of bias tool.
  
  
  RESULTS
  Sixteen of 695 nonduplicate records were analyzed (759 children with ADHD). When all types of training were considered together, there were significant effects on total ADHD (standardized mean difference [SMD] = 0.37, 95% CI = 0.09-0.66) and inattentive symptoms (SMD = 0.47, 95% CI = 0.14-0.80) for reports by raters most proximal to the treatment setting (i.e., typically unblinded). These figures decreased substantially when the outcomes were provided by probably blinded raters (ADHD total: SMD = 0.20, 95% CI = 0.01-0.40; inattention: SMD = 0.32, 95% CI = -0.01 to 0.66). Effects on hyperactivity/impulsivity symptoms were not significant. There were significant effects on laboratory tests of working memory (verbal: SMD = 0.52, 95% CI = 0.24-0.80; visual: SMD = 0.47, 95% CI = 0.23-0.70) and parent ratings of executive function (SMD = 0.35, 95% CI = 0.08-0.61). Effects on academic performance were not statistically significant. There were no effects of working memory training, specifically on ADHD symptoms. Interventions targeting multiple neuropsychological deficits had large effects on ADHD symptoms rated by most proximal assessors (SMD = 0.79, 95% CI = 0.46-1.12).
  
  
  CONCLUSIONS
  Despite improving working memory performance, cognitive training had limited effects on ADHD symptoms according to assessments based on blinded measures. Approaches targeting multiple neuropsychological processes may optimize the transfer of effects from cognitive deficits to clinical symptoms.
authors.affiliation: Developmental Brain-Behaviour Laboratory, University of Southampton, UK; School of Medicine, University of Nottingham, UK; New York University Child Study Center, New York.
authors.forename: Samuele
authors.initials: S
authors.lastname: Cortese
authors.affiliation: King's College London, Institute of Psychiatry, UK; Centro de Salud Mental de Estella, Navarra, Spain; Huntercombe Hospital Maidenhead, UK.
authors.forename: Maite
authors.initials: M
authors.lastname: Ferrin
authors.affiliation: Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Germany; University of Zurich, Switzerland.
authors.forename: Daniel
authors.initials: D
authors.lastname: Brandeis
authors.affiliation: Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, Nijmegen, The Netherlands; Karakter Child and Adolescent Psychiatry University Centre, Nijmegen.
authors.forename: Jan
authors.initials: J
authors.lastname: Buitelaar
authors.affiliation: School of Medicine, University of Nottingham, UK; School of Medicine, University of Nottingham, UK and the Centre for ADHD and Neurodevelopmental Disorders Across the Lifespan, Institute of Mental Health, University of Nottingham, UK.
authors.forename: David
authors.initials: D
authors.lastname: Daley
authors.affiliation: Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Germany.
authors.forename: Ralf W
authors.initials: RW
authors.lastname: Dittmann
authors.affiliation: LWL-University Hospital for Child and Adolescent Psychiatry, Ruhr University, Bochum, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Holtmann
authors.affiliation: King's College London, Institute of Psychiatry, UK.
authors.forename: Paramala
authors.initials: P
authors.lastname: Santosh
authors.affiliation: Developmental Brain-Behaviour Laboratory, University of Southampton, UK.
authors.forename: Jim
authors.initials: J
authors.lastname: Stevenson
authors.affiliation: King's College London, Institute of Psychiatry, UK.
authors.forename: Argyris
authors.initials: A
authors.lastname: Stringaris
authors.affiliation: Unit of Child Neuropsychiatry, University of Cagliari, Cagliari, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Zuddas
authors.affiliation: Developmental Brain-Behaviour Laboratory, University of Southampton, UK; Ghent University, Belgium; Aarhus University, Denmark. Electronic address: ejb3@soton.ac.uk.
authors.forename: Edmund J S
authors.initials: EJ
authors.lastname: Sonuga-Barke
mesh_terms: D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000628:therapy*; D002648:Child; D003071:Cognition; D015928:Cognitive Behavioral Therapy / Q000379:methods*; D055317:Evidence-Based Practice; D056344:Executive Function; D006801:Humans; D008570:Memory, Short-Term; D017594:Publication Bias; D016032:Randomized Controlled Trials as Topic; D016896:Treatment Outcome
keywords: ADHD; evidence-based psychiatry; executive functions; nonpharmacological; working memory