In the intervention trial, short sleep prevalence fell sharply in delayed-start schools (intervention 2: 40.47% to 11.87%) while sufficient-sleep prevalence remained low overall¶

Claim · All claims
Evidence · 1 study (2 entries) · causal r2 · q2
Currency · newest study 2013 · checked against its sources 2026-10-20 (automated, 2 of 2 entries) · not reviewed by a person

Subclaims¶

q2 i? Post-intervention, short sleep duration prevalence was 44.27% in control, 22.88% in intervention 1, and 11.87% in intervention 2 schools. → Li Shenghui 2013 q2 i? Despite the intervention, only a minority of children got the recommended 10 or more hours of sleep and approximately half still reported daytime sleepiness. → Li Shenghui 2013 (2)

Evidence¶

Li Shenghui 2013¶

Li Shenghui, Arguelles Lester, Jiang Fan, Chen Wenjuan, Jin Xingming, Yan Chonghuai, Tian Ying, Hong Xiumei, Qian Ceng, Zhang Jun, Wang Xiaobin, Shen Xiaoming. (2013). Sleep, School Performance, and a School-Based Intervention among School-Aged Children: A Sleep Series Study in China. PLoS ONE. https://doi.org/10.1371/journal.pone.0067928

q2 · i? · causal · r2

Post-intervention survey comparison across the three school groups in the intervention trial (Table 5, chi-square test). Short sleep prevalence was 44.27% (control), 22.88% (intervention 1), and 11.87% (intervention 2), a difference the table marks significant (χ2 = 23.04, p<0.001); no standardized effect size is printed.

"Short SD, n (%) 170 (44.27) 47 (22.88) 19 (11.87) 23.04*** b"

Li Shenghui 2013 (2)¶

Li Shenghui, Arguelles Lester, Jiang Fan, Chen Wenjuan, Jin Xingming, Yan Chonghuai, Tian Ying, Hong Xiumei, Qian Ceng, Zhang Jun, Wang Xiaobin, Shen Xiaoming. (2013). Sleep, School Performance, and a School-Based Intervention among School-Aged Children: A Sleep Series Study in China. PLoS ONE. https://doi.org/10.1371/journal.pone.0067928

q2 · i? · causal · r2

Authors' interpretation of the intervention trial outcome in the discussion: despite delayed start times, "only a minority of children got the recommended 10 or more hours of sleep" and about half still reported daytime sleepiness. This is the authors' stated caveat, not a separately tested result.

"it should be pointed out that only a minority of children got the recommended 10 or more hours of sleep and still approximately half of children continued to report daytime sleepiness after the change of the school start time."

Discussion¶

Learner Variables¶

• Sleep — outcome: instruction changes it

Related Claims¶

• Daytime sleepiness is highly prevalent among Chinese school-aged children, affecting 64.44% (sometimes 37.50%, frequently 26.94%) — related
• Delaying school start time by 30 or 60 minutes increased children's sleep duration and reduced daytime sleepiness over two years — a broader claim this one bears on
• Only 22.34% of Chinese school-aged children get sufficient sleep (≥10 hours), while 37.96% have short sleep duration (<9 hours) — related
• Frequent daytime sleepiness is associated with impaired academic achievement, attention, and learning motivation in school-aged children — related
• Sleep and consolidation support semantic memory development, suggesting delayed school start times may benefit memory — related
• Sleep problems are common in school-aged children, with prevalence estimates ranging widely depending on assessment mode and definition — a broader claim this one bears on