This study aims to evaluate the effectiveness of the trial of national multicentric school-based health lifestyles intervention toward childhood obesity on the KBP at individual, family and schools' levels.
The national trial was a multi-centered, cluster-controlled trial, which was conducted in seven provinces from September 2013 to February 2014, aiming at preventing childhood overweight and obesity. Integrated intervention strategies focused on changing specific practice related to energy intake and expenditure, such as decreasing the consumption of sweetened fizzy drinks, increasing the consumption of vegetables, ensuring proper protein intake, reducing sedentary practice including screen time, and maintaining at least 1 h of moderate to vigorous physical activity. A total of 27,477 children and adolescents in the control group and 30,997 in the intervention group were recruited with a mean follow-up period of 6.7 months. The binomial response mixed-effects model was used for assessing the effects of the national school-based health lifestyles intervention on obesity-related KBP at students individual, parents' and schools' levels.
Children and adolescents in the intervention group mastered better obesity-related knowledge, and they had higher correct response rates to all questions about obesity-related knowledge compared to the control group (
The obesity-related knowledge and beliefs of children and adolescents got improved significantly. However, the effects on the knowledge, beliefs and certain practices of their parents and school administrators failed to reach significance.