title: Evaluation of Internet-Based Interventions on Waist Circumference Reduction: A Meta-Analysis.
abstract: BACKGROUND
  Internet-based interventions are more cost-effective than conventional interventions and can provide immediate, easy-to-access, and individually tailored support for behavior change. Waist circumference is a strong predictor of an increased risk for a host of diseases, such as hypertension, diabetes, and dyslipidemia, independent of body mass index. To date, no study has examined the effect of Internet-based lifestyle interventions on waist circumference change.
  
  
  OBJECTIVE
  This study aimed to systematically review the effect of Internet-based interventions on waist circumference change among adults.
  
  
  METHODS
  This meta-analysis reviewed randomized controlled trials (N=31 trials and 8442 participants) that used the Internet as a main intervention approach and reported changes in waist circumference.
  
  
  RESULTS
  Internet-based interventions showed a significant reduction in waist circumference (mean change -2.99 cm, 95% CI -3.68 to -2.30, I(2)=93.3%) and significantly better effects on waist circumference loss (mean loss 2.38 cm, 95% CI 1.61-3.25, I(2)=97.2%) than minimal interventions such as information-only groups. Meta-regression results showed that baseline waist circumference, gender, and the presence of social support in the intervention were significantly associated with waist circumference reduction.
  
  
  CONCLUSIONS
  Internet-based interventions have a significant and promising effect on waist circumference change. Incorporating social support into an Internet-based intervention appears to be useful in reducing waist circumference. Considerable heterogeneity exists among the effects of Internet-based interventions. The design of an intervention may have a significant impact on the effectiveness of the intervention.
authors.affiliation: College of Health Sciences, Department of Health Education and Management, Ewha Womans University, Seoul, Republic Of Korea. dseo@ewha.ac.kr.
authors.forename: Dong-Chul
authors.identifier: http://orcid.org/0000-0002-1972-6237
authors.initials: DC
authors.lastname: Seo
authors.forename: Jingjing
authors.identifier: http://orcid.org/0000-0001-9812-2548
authors.initials: J
authors.lastname: Niu
mesh_terms: D000328:Adult; D001521:Behavior Therapy / Q000191:economics / Q000379:methods*; D015992:Body Mass Index; D003362:Cost-Benefit Analysis; D005260:Female; D006801:Humans; D020407:Internet; D008019:Life Style; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000175:diagnosis* / Q000191:economics / Q000628:therapy*; D016032:Randomized Controlled Trials as Topic; D012944:Social Support; D055105:Waist Circumference / Q000502:physiology*
keywords: Internet; adiposity; intervention studies; obesity; waist circumference