Objective: To examine the purchase behaviors of prepackaged food and its determinants among primary and middle school students in 6 provinces of China. Methods: A multi-stage sampling strategy was adopted to select 2 499 primary and middle school students and their parents from the eastern region of China(Beijing, Jiangsu Province, Guangdong Province), the northeast region(Heilongjiang Province), the central region(Henan Province) and the western region(Sichuan Province) from July 2020 to March 2021. Socio-demographic characteristics of students and their parents, eating-related behaviors and the purchase behaviors of prepackaged food of students, and parents' attitudes towards students' eating behavior were collected through questionnaire towards students and their parents. The χ² test was conducted to compare the purchase behaviors in different groups of students, and multivariate logistic stepwise regression analysis was used to analyze the determinants among primary and middle school students. Results: The age of 2 499 participants was(12.7±2.5) years. There were 1 272(50.9%) females and 1 279(51.2%) middle school students. About 1 404(56.2%) students bought prepackaged food. The top 6 prepackaged foods bought at least once a week were milk and dairy products(74.6%), baked food(58.7%), beverages(42.8%), puffed food(40.8%), chocolate and candy(39.8%), and nuts and dried fruits(37.5%). The multivariate logistic regression model analysis results showed that compared with primary school students, rural students, non-boarding students, students who did not like snacks and students whose parents paid attention to their children eating snacks, middle school students(OR=3.36, 95%CI:2.73-4.12), urban students(OR=1.33, 95%CI:1.11-1.61), boarding students(OR=2.15, 95%CI:1.66-2.79), students who liked snacks(OR=2.01, 95%CI:1.66-2.43), students whose parents did not pay attention to their children eating snacks(OR=1.27, 95%CI:1.05-1.54) were more likely to buy prepackaged food by themselves. Compared with students whose parents had education level of junior high school and below, students whose parents had education level of undergraduate and above(OR=0.70, 95%CI:0.53-0.92) were less likely to buy prepackaged food by themselves. Compared with students whose family monthly income was less than 5 000 yuan, students whose family monthly income was over 10 000 yuan(OR=0.67, 95%CI:0.52-0.87) were less likely to buy prepackaged food by themselves. Conclusion: Many primary and middle school students buy prepackaged food by themselves in 6 provinces of China. Individual characteristics such as grade, place of residence, boarding status, as well as family environment such as parents' education level, monthly income and concern about children eating snacks are the influencing factors of purchasing prepackaged food.
目的： 分析我国六省份中小学生预包装食品购买行为及其影响因素。 方法： 于2020年7月—2021年3月，采用多阶段抽样方法，在我国东部（北京、江苏、广东）、东北（黑龙江）、中部（河南）、西部（四川）共抽取2 499名中小学生及其家长开展调查。通过对学生和家长的问卷调查，收集中小学生和家长的基本信息、中小学生饮食相关态度和行为、中小学生预包装食品购买行为、家长对其饮食行为的态度等。采用χ²检验比较不同特征中小学生预包装食品购买行为，采用多因素logistic逐步回归分析中小学生预包装食品购买行为的影响因素。 结果： 2 499名研究对象年龄为（12.7±2.5）岁；女性1 272名（50.9%）；中学生1 279名（51.2%）；56.2%的中小学生自己购买预包装食品。中小学生每周至少购买1次预包装食品比例排前6位的依次是奶及奶制品（74.6%）、烘焙食品（58.7%）、饮料（42.8%）、膨化食品（40.8%）、巧克力和糖果（39.8%）和坚果和干果类（37.5%）。多因素logistic回归模型分析结果显示，与小学生、农村学生、非寄宿生、不喜欢吃零食者、家长关注孩子吃零食者相比，中学生（OR=3.36，95%CI：2.73~4.12）、城市学生（OR=1.33，95%CI：1.11~1.61）、寄宿生（OR=2.15，95%CI：1.66~2.79），喜欢吃零食（OR=2.01，95%CI：1.66~2.43）、家长不关注孩子吃零食（OR=1.27，95%CI：1.05~1.54）的学生自己购买预包装食品的可能性较高；与家长受教育程度为初中及以下的学生相比，家长受教育程度为大学本科及以上的学生购买预包装食品的可能性较低（OR=0.70，95%CI：0.53~0.92）；与家庭月收入<5 000元的学生相比，家庭月收入>10 000元的学生自己购买预包装食品的可能性较低（OR=0.67，95%CI：0.52~0.87）。 结论： 我国六省份中小学生购买预包装食品者较多；年级、居住地、是否寄宿等个体特征和家长受教育程度、月收入及其是否关注孩子吃零食等家庭环境是购买预包装食品的影响因素。.