我国青少年生活方式行为的追踪研究和干预机制分析

Developing strategies to reduce unhealthy dieting and sedentary time is well-proved to be beneficial for preventing the overweight and obesity rates in Chinese youth. However, the effects of existing individual-and group-based interventions are generally short-term and have only small impact on reducing sedentary time and unhealthy dieting, because: 1) determinants of behavior found to be related with overall physical or sedentary behavior as well as the total amount or type of eating, few considered the context-specific (i.e., time-stamped or location-specific) relationship between behaviors and factors; 2) the mediators of context-specific behavior which is appropriate to be intervened in as well as the interventional models are still not clear. To develop the effective interventions to reduce the sedentary time and unhealthy dieting, more research is required to understand the context-specific behavior patterns as well as the mediators. Therefore, our study will apply a longitudinal design to explore the context-specific and group-tailored interventions. We will use objective and subjective methods to accurately measure the physical activity, sedentary behavior and diet behavior. Moreover, we will use mixed research methods and both quantitative and qualitative research techniques to collect the determinants of behavior. Furthermore, a complex model based on the previous model including social ecological model、health belief model and theory of planned behavior will be tailored for Chinese youth, to explain the underlying behavioral mechanisms. Results of this research will guide the development of interventions to reduce the sedentary behavior and unhealthy diet, and the development of healthy policy to prevent overweight and obesity on Chinese youth.

减少青少年久坐不动的活动时间与不良饮食行为是预防我国青少年肥胖的重要干预手段，但研究表明现有的干预措施有效性低、效果短暂。主要原因在于1)当前研究发现和验证的环境和个人影响因素主要针对的是总体的青少年身体活动、静坐活动以及饮食行为，很少考虑行为的情境性（指具体时间和地点，比如课间或周末等不同情境下的身体活动行为）；2)对影响青少年行为的中介变量(mediator)和机制认识不清晰。为了制定有效的干预措施，需要更多的数据理解影响不同情境中行为的变量以及验证促进健康行为的中介变量和机制。因此，本纵向研究将采用定性和定量相结合的混合研究方法，利用主客观结合的测量手段追踪测量静坐活动和饮食行为模式；借助于社会生态模型、康信念理论与计划行为理论模型整合的理论模型，来获得关于影响行为的证据因素，并据此制定干预措施。研究结果将形成自主减少静坐活动和不良饮食的新模式，形成初步的青少年卫生政策建议。

探索有效的干预措施减少青少年久坐不动的活动时间与不良饮食行为同时增强其身体活动是预防我国青少年肥胖促进其身心健康的迫切需要，但研究表明现有的干预措施有效性低、效果短暂。主要原因在于：1）对不良健康生活方式的危险人群及其行为模式特征认识尚不清晰；2）对影响其具体情境中生活方式行为的因素认识不足；3）行为的长期监测和干预手段依从性较差。基于此，我们通过系统综述（荟萃分析）、实证研究与软件开发的办法，构建了追踪青少年生活方式行为、影响因素和健康结果的移动监测平台，用于管理追踪青少年生活方式行为及其健康状况。利用系统综述和二手资料，我们分析了影响我国居民饮食和身体活动行为的因素，分析了来自北京和安徽的共计1367名青少年的生活方式模式以及影响因素，将结果运用到移动技术平台的问卷和干预内容中。并且独立开发了健康管理的计算机系统、手机安卓和IOS的APP平台用于现场调查，将长期追踪青少年健康生活方式行为、影响因素及其健康状况。现场调查将在某高校教育集团的全国附属学校3省5个城市开展。本课题对我国青少年的行为模式及其影响因素进行了深入探索，同时为优化我国移动健康干预设计提供了理论和实践基础。