title: Sleep, school performance, and a school-based intervention among school-aged children: a sleep series study in China.
abstract: BACKGROUND
  Sufficient sleep during childhood is essential to ensure a transition into a healthy adulthood. However, chronic sleep loss continues to increase worldwide. In this context, it is imperative to make sleep a high-priority and take action to promote sleep health among children. The present series of studies aimed to shed light on sleep patterns, on the longitudinal association of sleep with school performance, and on practical intervention strategy for Chinese school-aged children.
  
  
  RESULTS
  A serial sleep researches, including a national cross-sectional survey, a prospective cohort study, and a school-based sleep intervention, were conducted in China from November 2005 through December 2009. The national cross-sectional survey was conducted in 8 cities and a random sample of 20,778 children aged 9.0±1.61 years participated in the survey. The five-year prospective cohort study included 612 children aged 6.8±0.31 years. The comparative cross-sectional study (baseline: n = 525, aged 10.80±0.41; post-intervention follow-up: n = 553, aged 10.81±0.33) was undertaken in 6 primary schools in Shanghai. A battery of parent and teacher reported questionnaires were used to collect information on children's sleep behaviors, school performance, and sociodemographic characteristics. The mean sleep duration was 9.35±0.77 hours. The prevalence of daytime sleepiness was 64.4% (sometimes: 37.50%; frequently: 26.94%). Daytime sleepiness was significantly associated with impaired attention, learning motivation, and particularly, academic achievement. By contrast, short sleep duration only related to impaired academic achievement. After delaying school start time 30 minutes and 60 minutes, respectively, sleep duration correspondingly increased by 15.6 minutes and 22.8 minutes, respectively. Moreover, intervention significantly improved the sleep duration and daytime sleepiness.
  
  
  CONCLUSIONS
  Insufficient sleep and daytime sleepiness commonly existed and positively associated with the impairment of school performance, especially academic achievement, among Chinese school-aged children. The effectiveness of delaying school staring time emphasized the benefits of optimal school schedule regulation to children's sleep health.
authors.affiliation: MOE - Shanghai Key Laboratory of Children's Environmental Health, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, PR China.
authors.forename: Shenghui
authors.initials: S
authors.lastname: Li
authors.forename: Lester
authors.initials: L
authors.lastname: Arguelles
authors.forename: Fan
authors.initials: F
authors.lastname: Jiang
authors.forename: Wenjuan
authors.initials: W
authors.lastname: Chen
authors.forename: Xingming
authors.initials: X
authors.lastname: Jin
authors.forename: Chonghuai
authors.initials: C
authors.lastname: Yan
authors.forename: Ying
authors.initials: Y
authors.lastname: Tian
authors.forename: Xiumei
authors.initials: X
authors.lastname: Hong
authors.forename: Ceng
authors.initials: C
authors.lastname: Qian
authors.forename: Jun
authors.initials: J
authors.lastname: Zhang
authors.forename: Xiaobin
authors.initials: X
authors.lastname: Wang
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Shen
mesh_terms: D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D002986:Clinical Trials as Topic; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D018479:Early Intervention, Educational / Q000706:statistics & numerical data; D004522:Educational Status; D005260:Female; D006801:Humans; D008297:Male; D015337:Multicenter Studies as Topic; D012574:Schools / Q000706:statistics & numerical data; D012890:Sleep / Q000502:physiology*; D012893:Sleep Wake Disorders / Q000453:epidemiology*