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Completed No phase listed Observational

Changing School Start Times: Impact on Student, Family, Teacher, and Community Health

ClinicalTrials.gov ID: NCT03964181

Public ClinicalTrials.gov record NCT03964181. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.

ClinicalTrials.gov public records Last synced Sep 4, 2026, 6:25 PM EDT

Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.

Brief summary

Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.

Sleep is not an optional luxury, but a fundamental biological need, essential for health and well-being. Insufficient sleep is a significant public health issue, with 69% of adolescents in America obtaining less than the minimum requirement of 8 hours of sleep per night. Early school start times has been identified as the most significant and modifiable factor that restricts sleep duration in adolescents. The American Academy of Pediatrics recommended in 2014 that all middle and high schools start no earlier than 8:30 a.m., yet few school districts have implemented this change. In fall 2017, the Cherry Creek School District, a diverse district of almost 55,000 students outside Denver, changed school start times. Although previous studies have shown increased sleep duration, decreased daytime sleepiness, and improved academics following start time changes for secondary students, there remains an urgent need to understand how this policy impacts health and well-being for all students, including youth in elementary school. Recognizing that students are part of a complex system that includes parents, school staff, and the community, this observational study will be a multi-year, broad-based evaluation that includes key stakeholders, multiple sources of quantitative data (i.e., surveys, academic records, district nursing electronic health records), contextual qualitative data (i.e., open-ended surveys and focus groups), and community-based outcomes (i.e., data on vehicle crashes and juvenile crimes). The primary hypothesis is that later school start times will have a positive impact on middle and high school students sleep and health outcomes, while earlier school start times will have a neutral impact on elementary school students sleep and health outcomes.

Study identification

NCT ID
NCT03964181
Recruitment status
Completed
Study type
Observational
Phase
Not listed
Lead sponsor
National Jewish Health
Other
Enrollment
118,000 participants

Conditions and interventions

Conditions

Interventions

Other

Eligibility (public fields only)

Age range
8 Years and older
Sex
All
Healthy volunteers
Not listed

This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.

Study timeline

Start date
Apr 10, 2017
Primary completion
May 30, 2019
Completion
Jul 30, 2021
Last update posted
Sep 28, 2022

2017 – 2021

United States locations

U.S. sites
1
U.S. states
1
U.S. cities
1
Facility City State ZIP Site status
National Jewish Health Denver Colorado 80206

Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.

About this trial record page

What this page shows
Public field values for ClinicalTrials.gov record NCT03964181, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
What this page does not do
No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
Where the data comes from
Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
Last refresh
Last update posted Sep 28, 2022 · Synced Sep 4, 2026

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Open the official record

The complete protocol, eligibility criteria, and contact information for NCT03964181 live on ClinicalTrials.gov.

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