title: Clinical review: behavioral interventions to prevent childhood obesity: a systematic review and metaanalyses of randomized trials.
abstract: BACKGROUND
  The efficacy of lifestyle interventions to encourage healthy lifestyle behaviors to prevent pediatric obesity remains unclear.
  
  
  OBJECTIVE
  Our objective was to summarize evidence on the efficacy of interventions aimed at changing lifestyle behaviors (increased physical activity, decreased sedentary activity, increased healthy dietary habits, and decreased unhealthy dietary habits) to prevent obesity.
  
  
  METHODS
  Data sources included librarian-designed searches of nine electronic databases, references from included studies and reviews (from inception until February 2006), and content expert recommendations.
  
  
  METHODS
  Eligible studies were randomized trials enrolling children and adolescents assessing the impact of interventions on both lifestyle behaviors and body mass index (BMI).
  
  
  METHODS
  Two reviewers independently abstracted data on methodological quality, study characteristics, intervention components, and treatment effects.
  
  
  METHODS
  We conducted random-effects metaanalyses, quantified inconsistency using I(2), and conducted planned subgroup analyses for each examined outcome.
  
  
  RESULTS
  Regarding target behaviors, the pooled effect size for physical activity (22 comparisons; n = 9891 participants) was 0.12 [95% confidence interval (CI) = 0.04-0.20; I(2) = 63%], for sedentary activity (14 comparisons; n = 3003) was -0.29, (CI = -0.35 to -0.22; I(2) = 0%), for healthy dietary habits (14 comparisons, n = 5468) was 0.00 (CI = -0.20; 0.20; I(2) = 83%), and for unhealthy dietary habits (23 comparisons, n = 9578) was -0.20 (CI = -0.31 to -0.09; I(2) = 34%). The effect of these interventions on BMI (43 comparisons, n = 32,003) was trivial (-0.02; CI = -0.06-0.02; I(2) = 17%) compared with control. Trials with interventions lasting more than 6 months (vs. shorter trials) and trials with postintervention outcomes (vs. in-treatment outcomes) yielded marginally larger effects.
  
  
  CONCLUSIONS
  Pediatric obesity prevention programs caused small changes in target behaviors and no significant effect on BMI compared with control. Trials evaluating promising interventions applied over a long period, using responsive outcomes, with longer measurement timeframes are urgently needed.
authors.affiliation: Knowledge and Encounter Research Unit, Mayo Clinic, W18A, 200 First Street SW, Rochester, Minnesota 55905, USA.
authors.forename: Celia C
authors.initials: CC
authors.lastname: Kamath
authors.forename: Kristin S
authors.initials: KS
authors.lastname: Vickers
authors.forename: Angela
authors.initials: A
authors.lastname: Ehrlich
authors.forename: Lauren
authors.initials: L
authors.lastname: McGovern
authors.forename: Jonathan
authors.initials: J
authors.lastname: Johnson
authors.forename: Vibha
authors.initials: V
authors.lastname: Singhal
authors.forename: Remberto
authors.initials: R
authors.lastname: Paulo
authors.forename: Allison
authors.initials: A
authors.lastname: Hettinger
authors.forename: Patricia J
authors.initials: PJ
authors.lastname: Erwin
authors.forename: Victor M
authors.initials: VM
authors.lastname: Montori
mesh_terms: D000293:Adolescent; D015992:Body Mass Index; D002648:Child; D002652:Child Behavior; D002675:Child, Preschool; D003627:Data Interpretation, Statistical; D005247:Feeding Behavior; D006801:Humans; D008019:Life Style; D009043:Motor Activity; D009765:Obesity / Q000517:prevention & control*; D011786:Quality Control; D016032:Randomized Controlled Trials as Topic / Q000592:standards / Q000706:statistics & numerical data; D012107:Research Design