Zheng Liu1, Pei Gao2, Ai-Yu Gao3, Yi Lin4, Xiang-Xian Feng5, Fang Zhang6, Li-Qun Xu7, Wen-Yi Niu8, Hai Fang9, Shuang Zhou1, Wen-Hao Li1, Jian-Hui Yuan5, Chun-Xia Xu4, Na Wu7, Hui-Juan Li10, Li-Ming Wen11, George C Patton12, Hai-Jun Wang1, Yang-Feng Wu2,10. 1. Department of Maternal and Child Health, School of Public Health, Peking University, National Health Commission Key Laboratory of Reproductive Health, Beijing, China. 2. Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, China. 3. Dongcheng Primary and Secondary School Health Care Center, Beijing, China. 4. Urumqi Primary and Secondary School Health Care Center, Xinjiang, China. 5. Changzhi Medical College, Shanxi, China. 6. Mentougou Primary and Secondary School Health Care Center, Beijing, China. 7. Center of Excellence for mHealth and Smart Healthcare, China Mobile Research Institute, China Mobile Communications Corporation, Beijing, China. 8. Department of Social Medicine and Health Education, School of Public Health, Peking University, Beijing, China. 9. China Center for Health Development Studies, Peking University, Beijing, China. 10. Peking University Clinical Research Institute, Beijing, China. 11. School of Public Health, Faculty of Medicine and Health, University of Sydney, Sydney, Australia. 12. Department of Paediatrics, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne, Australia.
Abstract
Importance: A rapid nutritional transition has caused greater childhood obesity prevalence in many countries, but the repertoire of effective preventive interventions remains limited. Objective: To determine the effectiveness of a novel multifaceted intervention for obesity prevention in primary school children. Design, Setting, and Participants: A cluster randomized clinical trial was conducted during a single school year (from September 11, 2018, to June 30, 2019) across 3 socioeconomically distinct regions in China according to a prespecified trial protocol. Twenty-four schools were randomly allocated (1:1) to the intervention or the control group, with 1392 eligible children aged 8 to 10 years participating. Data from the intent-to-treat population were analyzed from October 1 to December 31, 2019. Interventions: A multifaceted intervention targeted both children (promoting healthy diet and physical activity) and their environment (engaging schools and families to support children's behavioral changes). The intervention was novel in its strengthening of family involvement with the assistance of a smartphone app. The control schools engaged in their usual practices. Main Outcomes and Measures: The primary outcome was the change in body mass index (BMI; calculated as weight in kilograms divided by height in square meters) from baseline to the end of the trial. Secondary outcomes included changes in adiposity outcomes (eg, BMI z score, prevalence of obesity), blood pressure, physical activity and dietary behaviors, obesity-related knowledge, and physical fitness. Generalized linear mixed models were used in the analyses. Results: Among the 1392 participants (mean [SD] age, 9.6 [0.4] years; 717 boys [51.5%]; mean [SD] BMI, 18.6 [3.7]), 1362 (97.8%) with follow-up data were included in the analyses. From baseline to the end of the trial, the mean BMI decreased in the intervention group, whereas it increased in the control group; the mean between-group difference in BMI change was -0.46 (95% CI, -0.67 to -0.25; P < .001), which showed no evidence of difference across different regions, sexes, maternal education levels, and primary caregivers (parents vs nonparents). The prevalence of obesity decreased by 27.0% of the baseline figure (a relative decrease) in the intervention group, compared with 5.6% in the control group. The intervention also improved other adiposity outcomes, dietary, sedentary, and physical activity behaviors, and obesity-related knowledge, but it did not change moderate- to vigorous-intensity physical activity, physical fitness, or blood pressure. No adverse events were observed during the intervention. Conclusions and Relevance: The multifaceted intervention effectively reduced the mean BMI and obesity prevalence in primary school children across socioeconomically distinct regions in China, suggesting its potential for national scaling. Trial Registration: ClinicalTrials.gov Identifier: NCT03665857.
Importance: A rapid nutritional transition has caused greater childhood obesity prevalence in many countries, but the repertoire of effective preventive interventions remains limited. Objective: To determine the effectiveness of a novel multifaceted intervention for obesity prevention in primary school children. Design, Setting, and Participants: A cluster randomized clinical trial was conducted during a single school year (from September 11, 2018, to June 30, 2019) across 3 socioeconomically distinct regions in China according to a prespecified trial protocol. Twenty-four schools were randomly allocated (1:1) to the intervention or the control group, with 1392 eligible children aged 8 to 10 years participating. Data from the intent-to-treat population were analyzed from October 1 to December 31, 2019. Interventions: A multifaceted intervention targeted both children (promoting healthy diet and physical activity) and their environment (engaging schools and families to support children's behavioral changes). The intervention was novel in its strengthening of family involvement with the assistance of a smartphone app. The control schools engaged in their usual practices. Main Outcomes and Measures: The primary outcome was the change in body mass index (BMI; calculated as weight in kilograms divided by height in square meters) from baseline to the end of the trial. Secondary outcomes included changes in adiposity outcomes (eg, BMI z score, prevalence of obesity), blood pressure, physical activity and dietary behaviors, obesity-related knowledge, and physical fitness. Generalized linear mixed models were used in the analyses. Results: Among the 1392 participants (mean [SD] age, 9.6 [0.4] years; 717 boys [51.5%]; mean [SD] BMI, 18.6 [3.7]), 1362 (97.8%) with follow-up data were included in the analyses. From baseline to the end of the trial, the mean BMI decreased in the intervention group, whereas it increased in the control group; the mean between-group difference in BMI change was -0.46 (95% CI, -0.67 to -0.25; P < .001), which showed no evidence of difference across different regions, sexes, maternal education levels, and primary caregivers (parents vs nonparents). The prevalence of obesity decreased by 27.0% of the baseline figure (a relative decrease) in the intervention group, compared with 5.6% in the control group. The intervention also improved other adiposity outcomes, dietary, sedentary, and physical activity behaviors, and obesity-related knowledge, but it did not change moderate- to vigorous-intensity physical activity, physical fitness, or blood pressure. No adverse events were observed during the intervention. Conclusions and Relevance: The multifaceted intervention effectively reduced the mean BMI and obesity prevalence in primary school children across socioeconomically distinct regions in China, suggesting its potential for national scaling. Trial Registration: ClinicalTrials.gov Identifier: NCT03665857.