ArticleSleep2021
Changing school start times: impact on sleep in primary and secondary school students.
Article in Sleep, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to trial NCT03964181 (Changing School Start Times), which is not on this map. Cited by 29 papers.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Changing School Start Times: Impact on Student, Family, Teacher, and Community Health
Who cites it
29 citing papers in PubMed.
- Association between dim light melatonin onset predicted from gene expression profiles with sleep time and chronotype preference: A pilot study.Chronobiology international · 2025Trial
- Trial
- School start times and racial disparities in early adolescent sleep.Sleep health · 2026Article
- Inequities in sleep duration among gender and sexual minority adolescents.Sleep health · 2025Article
- The Relations between Children's Sleep and School Engagement: Moderation by Socioeconomic Status and Sex.Social development (Oxford, England) · 2025Article
- Afternoon to early evening bright light exposure reduces later melatonin production in adolescents.Npj biological timing and sleep · 2025Article
- Article
- The indirect effect of sleep quality on stress-related psychosocial outcomes in adolescents: an investigation across genders.Frontiers in psychology · 2025Article
- Individual, social, and environmental predictors of insomnia symptom trajectories in a population cohort of Australian adolescents aged 13 to 17 years.Sleep advances : a journal of the Sleep Research Society · 2025Article
- Instructional approach, sleep, and perceived academic well-being in adolescents during COVID-19: Evidence from the NESTED study.Sleep health · 2024Article
- Pre-pandemic circadian phase predicts pandemic alcohol use among adolescents.Journal of sleep research · 2024Article
- Extending weeknight sleep duration in late-sleeping adolescents using morning bright light on weekends: a 3-week maintenance study.Sleep advances : a journal of the Sleep Research Society · 2024Article
- The forbidden zone for sleep is more robust in adolescents compared to adults.Frontiers in sleep · 2024Article
- School start times and their association with rurality in British Columbia, Canada: An environmental scan.Sleep advances : a journal of the Sleep Research Society · 2024Article
- Article
- Impact of delaying high school start times on weight and related behaviors - the START study.Preventive medicine · 2023Article
- Article
- Early morning university classes are associated with impaired sleep and academic performance.Nature human behaviour · 2023Article
- A Naturalistic Actigraphic Assessment of Changes in Adolescent Sleep, Light Exposure, and Activity Before and During COVID-19.Journal of biological rhythms · 2022Article
- Self-reported sleep and circadian characteristics predict alcohol and cannabis use: A longitudinal analysis of the National Consortium on Alcohol and Neurodevelopment in Adolescence Study.Alcoholism, clinical and experimental research · 2022Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
4 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
STUDY
objectivesTo examine the impact of changing school start times on sleep for primary (elementary school: ES) and secondary (middle and high school: MS/HS) students.
methodsStudents (grades 3-12) and parents (grades K-12) were surveyed annually, before and for 2 years after school start time changes (ES: 60 min earlier, MS: 40-60 min later; HS: 70 min later). Student sleep and daytime sleepiness were measured with school-administered student surveys and parent-proxy online surveys.
resultsApproximately 28,000 students annually completed surveys (~55% White, ~21% free/reduced lunch [FRL]). One-year post-change, weekday bedtimes and wake times were slightly earlier for ES students, with an 11-min decrease in sleep duration. MS and HS students reported slightly later weekday bedtimes, significantly later wake times, and significantly longer sleep duration (MS: 29 min; HS: 45 min). The percent of ES students reporting sufficient sleep duration, poor sleep quality, or daytime sleepiness did not change, but the percent of MS and HS students reporting sufficient sleep duration significantly increased and clinically significant daytime sleepiness decreased. All results were maintained at the 2-year follow-up. Benefits of later start times were similar across racial and free/reduced lunch groups.
conclusionsThis is the first large scale, longitudinal, and representative study to concurrently examine the impact of changing school start times across students in primary/secondary school. Findings suggest a minimal impact of earlier start times on ES students' sleep or daytime sleepiness, while further supporting the significant benefits of delaying MS and HS start times on student sleep and daytime sleepiness.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.