Limitations of studies on school-based nutrition education interventions for obesity in China: a systematic review and meta-analysis

Asia Pac J Clin Nutr. 2016;25(3):589-601. doi: 10.6133/apjcn.092015.19.


Background and objectives: School-based nutrition education has been widely implemented in recent years to fight the increasing prevalence of childhood obesity in China.

Methods and study design: A comprehensive literature search was performed using six databases to identify studies of school-based nutrition education interventions in China. The methodological quality and the risk of bias of selected literature were evaluated. Stratified analysis was performed to identify whether different methodologies influenced the estimated effect of the intervention.

Results: Seventeen articles were included in the analysis. Several of the included studies had inadequate intervention duration, inappropriate randomization methods, selection bias, unbalanced baseline characteristics between control and intervention groups, and absent sample size calculation. Overall, the studies showed no significant impact of nutrition education on obesity (OR=0.76; 95% CI=0.55-1.05; p=0.09). This can be compared with an OR of 0.68 for interventions aimed at preventing malnutrition and an OR of 0.49 for interventions aimed at preventing iron-deficiency anemia. When studies with unbalanced baseline characteristics between groups and selection bias in the study subjects were excluded, the impact of nutrition education on obesity was significant (OR=0.73; 95% CI=0.55-0.98; p=0.003). An analysis stratified according to the duration of intervention revealed that the intervention was effective only when it lasted for more than 2 years (OR=0.49, 95% CI=0.42-0.58; p<0.001).

Conclusion: Studies of school-based nutrition education programs in China have some important limitations that might affect the estimated effectiveness of the intervention.

背景与目的:面对近年来小学生肥胖发病率的不断增长,基于学校的营养教 育在中国广泛开展。方法与研究设计:利用万方、CNKI、CBM、Pubmed、 ISI Web of Knowledge 和Embase 六个数据库,对中国基于学校针对小学生肥 胖的营养教育的相关文献进行检索。对纳入的文献进行方法学和偏倚风险的评 估,并采用分层分析的方法探索不同方法是否会对干预效果的评估产生影响。 结果:共有17 篇文献纳入分析,其中有几个研究存在干预时间不足、随机化 方法不当、选择偏倚、干预组和对照组某些基线特征不均衡,以及缺乏样本量 的计算等问题。总体而言,相对于针对小学生营养不良的基于学校的营养教育 干预结果OR 为0.68,以及缺铁性贫血的干预结果OR 为0.49,基于学校的营 养教育对小学生肥胖没有显著影响( OR=0.76 , 95% CI=0.55-1.05 ; p=0.09)。当排除存在研究对象组间某些基线特征不均衡和选择偏倚的相关文 献后, 再次分析发现营养教育对肥胖的干预效果显著( OR=0.73 , 95% CI=0.55-0.98;p=0.003)。另外,根据干预时间进行分层分析,我们发现只有 当干预时间>2 年时,基于学校的营养教育才对小学生的肥胖有效(OR=0.49, 95% CI=0.42-0.58;p<0.001)。结论:中国基于学校的针对小学生肥胖的研究 有一些重要的局限性,可能会影响干预效果的评估。.

Publication types

  • Meta-Analysis
  • Review
  • Systematic Review

MeSH terms

  • Adolescent
  • Bias
  • Child
  • China / epidemiology
  • Feeding Behavior
  • Female
  • Health Education
  • Humans
  • Male
  • Nutritional Sciences / education*
  • Pediatric Obesity / epidemiology
  • Pediatric Obesity / prevention & control*
  • Randomized Controlled Trials as Topic
  • School Health Services*
  • Schools