ArticlePreventive medicine2023
Impact of delaying high school start times on weight and related behaviors - the START study.
Article in Preventive medicine, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 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.
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Who cites it
2 citing papers in PubMed, 4 citations in OpenAlex.
- Lifestyle Behaviors Associated with Weight Loss Intent in Adolescent Girls: Findings from the US 2021 National Youth Risk Behavior Survey.Nutrients · 2025Article
- [Overview of chronobiological and sleep medical aspects of depression in adolescents].Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz · 2024Review
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Authors and funding
9 authors at 2 institutions in 1 country.
Funding
Abstract
In the US, few adolescents get adequate school night sleep, largely due to early school start times. In the START study we aimed to test the following hypothesis: That following the implementation of later high school start times students have lesser longitudinal increases in body mass index (BMI) and shift to more healthful weight-related behaviors relative to students attending schools that retain early start times. The study enrolled a cohort of students (n = 2426) in five high schools in the Twin Cities, MN metro. Heights and weights were measured objectively, and surveys were administered annually from 9th through 11th grades (2016-2018). All study schools started early (either 7:30 am or 7:45 am) at baseline (2016). At follow-up 1 (2017) and continuing through follow-up 2 (2018), two schools delayed their start times by 50-65 min, while three comparison schools started at 7:30 am throughout the observation period. Using a difference-in-differences natural experiment design, we estimated differences in changes in BMI and weight-related behaviors over time between policy change and comparison schools. Students' BMIs increased in parallel in both policy change and comparison schools over time. However relative to changes in comparison schools after the start time shift, students in policy change schools had a modestly more healthful profile of weight-related behaviors - for instance they had a relatively greater probability of eating breakfast, having supper with their family, getting more activity, eating fast food less frequently, and eating vegetables daily. Later start times could be a durable, population-wide strategy that promotes healthful weight behaviors.
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Registered trials
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