【作者】 王文；

【导师】 史慧静；

【作者基本信息】 复旦大学 ， 公共卫生（专业学位）， 2013， 硕士

【摘要】 研究背景当今,超重肥胖、视力不良是学术界公认的在中小学生中存在的主要的健康问题。青少年亚健康近来也成为研究的重点和热点。导致青少年超重肥胖、视力不良、亚健康的因素很多也很复杂,其中静态行为对于青少年健康的影响最近才成为研究热点。静态行为是指久坐的行为活动模式,对中小学生来说静态活动包括每天的读写学习、阅读书籍印刷品、坐着交通、看电视、玩电脑、手机等电子产品等行为。一般来说,青少年在学校的静态行为相对比较固定和一致,而在课外的静态行为存在更多差异。因此本研究重点在于课外的静态行为。课外静态行为主要研究：1)完成各类书面家庭作业,2)用电脑学习,3)娱乐性屏前静态行为时间(以下简称“屏前时间”),4)看印刷的书籍报刊。在这之中,坐着或躺着看电视、玩电脑、手机等电子产品等的静态行为又称为屏前静态行为。大量研究致力于解释静态行为、体力活动与肥胖三者之间的关系。国外教育部门已经开始重视对静态行为的干预,干预的重点在书面作业时间和屏前时间。国内教育部门针对学生书面作业时间的干预已经开展,但是针对屏前时间的干预还未开展。研究目的本次横断面调查以及分析研究希望达到以下几个目的：调查上海市中小学生的静态行为模式。初步了解不同静态行为时间特别是书面作业时间和娱乐性屏前静态行为时间对学生健康结局指标的关联,分析它们对青少年健康的影响及其特点。找出静态行为时间过长与睡眠不足关联,书面做作业时间、屏前娱乐性静态行为时间过长学生组的人口学特征和其他一些特征,为下一步有针对性提出有效的干预手段提供科学依据。对象与方法被调查对象由上海市小学生、初中生组成,年龄范围在9-16岁。采用多阶段整群抽样方法选择调查对象。首先用简单随机抽样从全上海市8个中心城区选择2个区,在9个上海外围城区随机选择2个区。每个区采用系统抽样的方法,选择普通小学3所和初中3所。共计普通中小学24所。所选学校确定以后,每个学校每个年级以班级为单位整群抽样选取100-120名左右学生进行调查。按此方法,总共来自4个区、24所中小学校约6500名学生及其家长参与调查。学生和家长的问卷一一对应、编码,录入前再次清理及核对问卷,建立EpiData数据库和核查文件,对实际收到的问卷进行了数据录入及导出。数据分析采用SPSS16.0软件包。分析主要分为三部分,1.描述性分析,分析被调查对象的基本信息、学生各项健康指标、学生静态行为时间构成及差异。2.采用相关分析与t检验,卡方检验研究各种静态行为之间、静态行为与睡眠时间之间的相关系数、健康与各种静态行为的关联,作业时间和屏前娱乐性静态行为过长、睡眠不足学生组的特征。3.采用logistics回归分析研究书面作业时间和娱乐性屏前时间超时对青少年超重肥胖、视力不良、亚健康的危险度。结果四至八年学生级除课外阅读时间有所下降外,其他静态行为时间及总静态行为时间都是呈现上升趋势的。平均每日屏前娱乐时间离散度最大。平均每日总静态行为时间与平均每日睡眠时间的相关系数为-0.181,p<0.01。其中书面作业时间与每天睡眠时间(-0.23,p<0.01)、书面作业时间与屏前娱乐时间(-0.165,p<0.01)、书面作业时间与用电脑学习时间(-0.118,p<0.01)、屏前娱乐时间与用电脑学习时间(0.246,p<0.01)的相关系数较大且有统计学意义。学生每日作业时间过长的报告率为82.90%。外围城区比中心城区高5.8%,独生子女比非独生子女高3.5%,父母双方至少一方本科以及以上的学生组比父母双方均本科以下的学生组高4.2%。父母双方至少有一方正常工作学生组比父母双方均无工作学生组高8%。自感学习成绩优良和自感学习压力小的学生组报告率显著低于自感学习成绩差和自感学习压力大的学生。学生总体每日平均娱乐性屏前时间超过1小时报告率为26.4%,男生比女生高5.9%、中心城区比外围城区高5.7%、非独生子女比独生子女高8.7%、父母双方至少一方本科以及以上的学生组比父母双方均本科以下的学生组高13.6%、父母均无正常工作的比有父母一方有正常工作的高14.6%,自感学习成绩越差的学生报告率越高,同时每日平均娱乐性屏前时间超过1小时的报告率随年级升高有上升趋势中小学生总睡眠不足率15.5%,女生较男生高2.8%、外围城区较中心城区高2.6%、自感学习成绩差压力大的学生高于自感成绩好压力小的学生。屏前时间过长对青少年健康的影响主要表现在视力(adjOR:1.24,95%CI:1.055-1.456)和亚健康状态(adjOR:1.241,95%CI:1.078～1.428)上。书面作业对青少年健康的影响主要表现在亚健康状态(adjOR:1.273,95%CI:1.137～1.614)上。睡眠不足主要对亚健康(adjOR:1.935,95%CI:1.646～2.276)、超重肥胖(adjOR:1.396,95%CI:1.173～1.661)有显著的负面影响。讨论与结论不同地域、性别的中小学生,校园外静态行为模式存在差异。书面作业时间、娱乐性屏前时间过长对健康的影响特点不同,书面作业时间主要是通过挤压睡眠时间和直接影响健康(亚健康),而睡眠不足会导致健康问题(超重肥胖、亚健康)；娱乐性屏前时间直接影响健康(视力、亚健康)书面作业时间、娱乐性屏前时间过长的学生都有一定的特征,应进行重点人群干预。减轻学生的课外学习负担,特别注意的群体特征有外围城区、高年级、自感学习成绩差、学习压力大、男生。对于减少学生屏前时间的干预,应重点注意发达地区、非独生子女、高年级男生、自感学习成绩差、家庭社会经济地位低下的学生。保证学生睡眠时间,特别注意高年级、外围城区、自感学习成绩差、学习压力大的女生。屏前时间过长更多表现为个体差异(离散度大),且屏前静态行为对青少年的健康危害更大,应该特别重视对屏前静态行为时间的干预。更多还原

【Abstract】 BackgroundToday, it is accepted in academia that overweight and poor vision are major health problems in the primary and middle school students. Recently, youth sub-health has also become the focus and hot spots of research. The factors that lead to adolescent overweight, poor eyesight and sub-health are very complex. Health damage effects of the sedentary behavior for young people have only recently become the hot topic. Sedentary behavior refers to long-term sitting behavior patterns. For primary and middle school students, when they are learning, reading, watching TV, being in traffic, playing computer games, playing mobile phone and other electronic products are all sedentary behaviors. Generally speaking, the sedentary behavior of adolescents in school is relatively fixed but there are more differences outside class. So, our research focused on the sedentary behavior outside class. Studies of the extracurricular sedentary behavior of are mainly focus on:1) doing homework2) computer studies3) entertainment screen4) reading printed books, newspapers and magazines. Entertainment screen sedentary behavior refers to sitting while watching TV, playing computer games, cell phones and other electronic products. A large number of research studied sedentary behavior, physical activity and obesity in order to explain the relationship between the three. Foreign education sectors have begun to pay attention to the sedentary behavior intervention, which focus on the time of written assignments and entertainment screen sedentary behavior. Domestic education sectors’ interventions have been carried out against the students’studying burden about the time of written assignments, but for the time of entertainment screen sedentary behavior the interventions have not been carried out.ObjectivePurposes of this cross-sectional survey include:①Investigates the sedentary behavior of primary and middle school students in Shanghai.②Preliminary understands the association between different sedentary behavior (especially the time of written work and entertainment screen sedentary behavior) and healthy status, and analyses the effects and characteristics of sedentary behavior on the health status of adolescent.③Finds the demographic and other characteristics of the student group whose written homework or entertainment screen time is too long, and explores the roles of domestic discipline to intervene entertainment screen time in order to provide scientific basis for next effective targeted interventions.MethodsSelected by multi-stage cluster sampling, about6,500students and their parents from24primary and. secondary schools in4districts of Shanghai are participated in the survey. Students’ and parents’ questionnaires are coded one-to-one correspondence. We cleaned and checked questionnaire before entry, established the Epi-Data database and verification of documents, and entered data and exported. Data analysis was performed using SPSS16.0software package.The analysis is constituted by three parts:①Descriptive analysis is used for the basic information of the survey, various health indicators information of students, time composition and the difference of the sedentary behavior of students.②Using correlation analysis, t-test, and chi-square test to study the correlation coefficient of various "sedentary behavior", the demographic and other characteristics of the student group whose written homework or entertainment screen time is too long and lack of sleep.③Apply logistics regression analysis to study the OR(CI) and adj OR(CI) of lack of sleep, too long written homework time, too long entertainment screen time to adolescent overweight and obesity, poor vision, and sub-health risk.ResultsThe sedentary behaviors time and total sedentary behavior time of students (from grades four to eight) were showing an upward trend in addition to extracurricular reading time. The dispersion of average daily entertainment screen time was the highest. Correlation coefficient between average daily total sedentary behavior time and average daily sleep time was-0.181, p<0.01, written time and daily sleep time was-0.23(p<0.01), written assignments time and entertainment screen time was-0.165(p<0.01), written work time and computer learning time was-0.118(p<0.01), entertainment screen entertainment time and computer learning time was0.246(p<0.01), which were relatively large and statistically significant.The rate of students report too long written work time was82.90%. The report rate of students report too long written work time for peripheral urban areas was5.8% higher than the central urban area, the only-child family was3.5%higher than non-only-child family, students whose parents at least one got bachelor’s degree or above was4.2%higher than students whose parents did not, students whose parents at least one has normal work was8%higher than students whose parents neither gets normal work. The report rate of students who feel excellent in academic and low study pressure was significantly lower than the students who feel poor in academic performance and high study pressure.The rate of students report too long entertainment screen time was26.4%. There was an upward trend in reporting rate with grade level. The report rate of peripheral urban areas was5.7%higher than the central urban area, boys were5.9%higher than girls, the only-child was8.7%higher than non-only-child, students whose parents at least one got bachelor’s degree or above was13.6%higher than students whose parents neither got below bachelor’s degree. Students whose parents at least one has normal work was14.6%higher than students whose parents neither gets normal work. The report rate of students who feel poor in academic performance was significantly higher than the students who feel excellent in academic.The lack of sleep rate of primary and secondary students was15.5%, the report rate of girls was2.8%higher than that of boys, peripheral urban areas was2.6%higher than the central urban area.The report rate of students who feel excellent in academic and low study pressure was significantly lower than the students who feel poor in academic performance and high study pressure.The risk of too long entertainment screen time to adolescent health was mainly manifested in the vision (adjOR:1.24,95%CI:1.055～1.456) and sub-health state (adjOR:1.241,95%CI:1.078～1.428). The risk of too long written assignments time to adolescent health was mainly manifested in the sub-health state (adjOR:1.273,95%CI:1.137～1.614). The risk of lack of sleep to adolescent health was mainly manifested in the sub-health state (adjOR:1.935,95%CI:1.646～2.276) and overweight and obesity (adjOR:1.396,95%CI:1.173～1.661)ConclusionSedentary behavior patterns are different among areas of the different levels of economic development.The too long written assignments time and the too long entertainment screen time have different adverse effects on the health. The adverse effects of written work time is mainly by squeezing the sleep time and has a direct adverse impact on health (sub-health), and lack of sleep can lead to health problems (overweight and obesity, sub-health); entertainment screen time has a direct adverse impact on the health (vision and sub-health).The students whose written assignments time and entertaining screen time were too long have certain characteristics. We should focus on the population-based interventions. For reducing students’ extracurricular academic burden, we should pay more attention to groups characterized by underdeveloped areas、high-grade、poor academic performance、high study pressure、boys. For reducing screen sedentary time, we should focus on the groups characterized by developed areas、non-only child、 high-grade boys、poor academic performance、low socio-economic status. For ensuring student’s sleep time, we should pay more attention to the groups characterized by high-grade, peripheral urban areas, poor academic performance, high study pressure girls.Too long entertainment screen time is mainly expressed in individual differences (the dispersion is comparatively large) and is more dangerous to adolescent’s health. So, we should pay more attention to the intervention of entertaining screen time.更多还原