title: A systematic review and meta-analysis of social cognitive theory-based physical activity and/or nutrition behavior change interventions for cancer survivors.
abstract: OBJECTIVE
  Little is known about how to improve and create sustainable lifestyle behaviors of cancer survivors. Interventions based on social cognitive theory (SCT) have shown promise. This review examined the effect of SCT-based physical activity and nutrition interventions that target cancer survivors and identified factors associated with their efficacy.
  
  
  METHODS
  A systematic search of seven databases identified randomized controlled trials that (i) targeted adult cancer survivors (any point from diagnosis); (ii) reported a primary outcome of physical activity, diet, or weight management; and (iii) included an SCT-based intervention targeting physical activity or diet. Qualitative synthesis and meta-analysis were conducted. Theoretical constructs and intervention characteristics were examined to identify factors associated with intervention efficacy.
  
  
  RESULTS
  Eighteen studies (reported in 33 publications) met review inclusion criteria. Meta-analysis (n = 12) revealed a significant intervention effect for physical activity (standardized mean difference (SMD) = 0.33; P < 0.01). Most studies (six out of eight) that targeted dietary change reported significant improvements in at least one aspect of diet quality. No SCT constructs were associated with intervention effects. There were no consistent trends relating to intervention delivery method or whether the intervention targeted single or multiple behaviors.
  
  
  CONCLUSIONS
  SCT-based interventions demonstrate promise in improving physical activity and diet behavior in cancer survivors, using a range of intervention delivery modes. Further work is required to understand how and why these interventions offer promise for improving behavior.
  
  
  CONCLUSIONS
  SCT-based interventions targeting diet or physical activity are safe and result in meaningful changes to diet and physical activity behavior that can result in health improvements.
authors.affiliation: School of Medicine and Public Health, University of Newcastle, W4, HMRI Building, Callaghan, NSW, 2308, Australia, fiona.stacey@newcastle.edu.au.
authors.forename: Fiona G
authors.initials: FG
authors.lastname: Stacey
authors.forename: Erica L
authors.initials: EL
authors.lastname: James
authors.forename: Kathy
authors.initials: K
authors.lastname: Chapman
authors.forename: Kerry S
authors.initials: KS
authors.lastname: Courneya
authors.forename: David R
authors.initials: DR
authors.lastname: Lubans
mesh_terms: D000328:Adult; D001521:Behavior Therapy / Q000379:methods*; D003071:Cognition / Q000502:physiology; D015928:Cognitive Behavioral Therapy / Q000379:methods*; D003131:Combined Modality Therapy; D004032:Diet; D005247:Feeding Behavior / Q000502:physiology*; D006801:Humans; D007398:Interpersonal Relations; D008019:Life Style; D009043:Motor Activity / Q000502:physiology*; D009369:Neoplasms / Q000401:mortality / Q000534:rehabilitation*; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data; D017741:Survivors / Q000523:psychology