Objective   To examine the prevalence and influencing factors of sleep duration among school-age children in Hainan province for improving sleep quality of the children.

  Methods   Totally 25 162 children aged 6 – 12 years in 86 primary schools in Hainan province were recruited with stratified multistage random sampling. A self-designed questionnaire on demographics, sleep time and its associates was answered online by the children′s parents during November 2021 – January 2022. Logistic regression model was used to explore influencing factors of insufficient sleep in the children.

  Results  For the 24 200 children included in the final analysis, the parents-reported average weekday and weekend nighttime sleep time were 8.79 ± 0.81 and 9.51 ± 0.98 hours and the average total sleep time were 10.06 ± 1.18 and 11.62 ± 1.20 hours, respectively. Based on the parents′ reports, the prevalence of insufficient sleep (total sleep time < 10 hours/per day) was 30.8% and the prevalence linearly increased significantly with the increment of age among the children (P < 0.05). Logistic regression model analysis showed that the children with following characteristics were at significantly increased risk of having insufficient sleep time: aged 11 – 12 years (versus aged 6 – 7 years: odds ratio OR = 1.59, 95% confidence interval 95%CI: 1.43 – 1.77); with paternal education of college and above (versus primary school: OR = 1.36, 95%CI: 1.15 – 1.60); from core families (versus from families of other types: OR = 1.13, 95%CI: 1.01 – 1.26) or from stem families (versus from families of other types: OR = 1.14, 95%CI: 1.04 – 1.36); having daily outdoor sports time of less than one hour (versus 2 hours and more: OR = 1.69, 95%CI: 1.42 – 2.00); and having daily screen exposure time of 2 hours and longer (versus that of less than one hour: OR = 1.34, 95%CI: 1.18 – 1.51).

  Conclusion  Insufficient sleep time, especially insufficient nighttime sleep time, is prevalent among school-age children in Hainan province and at elder age, with higher paternal education, from core or stem families, less outdoor sports time, and longer screen exposure time are significant risk factors for insufficient sleep time in the school-age children.