Abstract: Objective To demonstrate the interaction effect of outdoor physical activity and extra-curricular cultural classes before primary school on poor vision of primary and middle school students, so as to provide scientific basis for formulating strategies and measures to prevent and control poor vision of primary and secondary school students. Methods A stratified cluster random sampling method was used for cross-sectional study from September to November 2018. A total of 8 467 students from fourth grade to senior three grade in Hunan Province completed the physical examination and questionnaire survey.Multivariate Logistic regression was used to explore the interactive effect of outdoor physical activity and extra-curricular cultural class before primary school on poor vision, also relative excess risk of interaction (RERI), attributable proportion of interaction (API), interaction index S (Index S) were calculated to demonstrate the interaction. Results Among the 8 467 subjects, 5 612(66.28%) children had poor vision. Compared with those who did not attend extra-curricular cultural classes, those who attended had a significantly higher risk of poor vision (OR=1.500, 95%CI:1.331—1.689, P<0.001). Compared with those whose outdoor physical activity ≥ 2 h/day, those whose outdoor physical activity < 2 h/day had a significantly higher risk of poor vision (OR=1.247, 95%CI:1.103—1.409, P<0.001). There was a significant interaction between outdoor physical activity and extra-curricular cultural classes before primary school on poor vision (P_interaction=0.003). With the potential covariates adjusted, the values of indicators (RERI, API, Index S) for interaction between outdoor physical activity and taking extra-curricular cultural classes before school age were 0.529, 0.310 and 3.973, respectively. Conclusions Both outdoor physical activities and extra-curricular cultural classes before primary school are associated with poor vision. In addition, they have an interactive effect on poor vision. Therefore, it is supposed to do more outdoor activities for preschoolchildren thereby reducing the prevalence of poor vision.

Key words: poor vision, outdoor activities, extra-curricular cultural courses, interaction

摘要： 目的 分析户外活动时间与学龄前参加文化课学习情况的交互作用与中小学生视力不良的关系,为制定防控中小学生视力不良的策略和措施提供科学依据。方法 采用分层整群随机抽样法于2018年9-11月在湖南省抽取8 467名小学四年级到高中三年级学生进行体格检查和问卷调查。相乘交互作用建立多因素Logistic回归模型,并计算交互作用超额危险度(RERI)、交互作用归因比(API)及交互作用指数 S (Index S)探讨户外活动时间与学龄前文化课学习对视力不良的相加交互作用。结果 8 467名调查对象中视力不良检出人数为5 612名,检出率为66.28%。学龄前参加过文化课学习者,视力不良的发生风险是不参加学习者的1.500倍(95%CI:1.331~1.689,P<0.001),每日户外活动<2 h的学生发生视力不良的风险是每日户外活动≥2 h者的1.247倍(95%CI:1.103~1.409,P<0.001)。户外活动时间与学龄前文化课学习的交互作用项具有统计学意义(P_交互=0.003)。在调整相关因素后,户外活动时间与学龄前文化课学习的RERI、API、Index S分别为0.529、0.310、3.973。结论 中小学生户外活动时间、学龄前文化课学习均与视力不良发生风险相关,并两者对视力不良有交互作用。因此,应加强学龄前儿童的户外活动,以预防视力不良发生。

关键词: 视力不良, 户外活动, 文化课学习, 交互作用