Effects of Delayed School Start Times on Sleep, Mental Health, and Academic Performance Among Norwegian Adolescents

NCT06657482 | Completed

• 1 other identifier: REK Vest 606094
• Study Type: interventional
• Target: 583
• Locations: 1 country
• Sites: 1

Brief Summary

The aim is to investigate whether later school start times have positive effects on high school students' sleep patterns, mental health and daytime functioning.

Conditions

Sleep; Sleep Disorders, Circadian Rhythm; Psychiatric Disorder; Sleepiness, Daytime

Outcome Measures

Primary Outcomes (3)

• Average sleep duration on school days

  Average sleep duration across the arms will be calculated using the Munich ChronoType Questionnaire (MCTQ), adjusted for nocturnal awakenings

  Baseline and at the end of the school year (at about 8 months follow-up)

• Preferred school start time (late vs. early Mondays and Tuesdays)

  A conditioned item asking how satisfied the students are starting early or later on Mondays and Tuesdays, or ranging from "Very satisfied" to "very dissatisfied", will be included.

  At the end of the school year (at about 8 months follow-up)

• Daytime sleepiness on school days

  Daytime sleepiness will be assessed based on the Karolinska Sleepiness Scale (KSS; adjusted to target sleepiness on each weekday) and The Chinese adolescent daytime sleepiness scale (CADSS).

  CADSS: Baseline and at the end of the school year (at about 8 months follow-up). KSS: At the end of the school year (at about 8 months follow-up)-up

Secondary Outcomes (4)

• School absence and academic performance (self-reported and objective)

  Self-reported data: Baseline and end of school year. Objective data: At the end of the school year (at about 8 months follow-up)-up

• Mental health

  Baseline and at the end of the school year (at about 8 months follow-up)

• Social jetlag

  Baseline and at the end of the school year (at about 8 months follow-up)

• Sleep duration, school days with early vs. late start

  At the end of the school year (at about 8 months follow-up)

Study Arms (2)

Delayed school start times on Mondays and Tuesdays (intervention condition)

EXPERIMENTAL

Two hour delay in school start time on Mondays and one hour delay on Tuesdays. Ordinary school start time (8:15 ± 15 min) for the rest of the week.

Behavioral: Delayed school start time

Ordinary school start time all weekdays (control condition)

NO INTERVENTION

Ordinary school start time (8:15 ± 15 min) all school days

Interventions

Delayed school start time BEHAVIORAL

The intervention group will start school two hours later on Mondays (at 10.15 ± 15 min) and one hour later on Tuesdays (9.15 ± 15 min) and to ordinary school start time (8.15 ± 15 min) for the rest of the week

Delayed school start times on Mondays and Tuesdays (intervention condition)

Eligibility Criteria

• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)

You may qualify if:

• st year high school students at study preparatory program of participating schools

You may not qualify if:

• Parent consent not obtained/documented for participants under 16 years

Sponsors & Collaborators

• Haukeland University Hospital: collaborator
• University of Bergen: lead

Study Sites (1)

University of Bergen

Bergen, Vestland, 5019, Norway

Location

MeSH Terms

Conditions

Sleep Disorders, Circadian Rhythm; Mental Disorders; Disorders of Excessive Somnolence

Condition Hierarchy (Ancestors)

Chronobiology Disorders; Nervous System Diseases; Dyssomnias; Sleep Wake Disorders; Occupational Diseases; Sleep Disorders, Intrinsic

Study Officials

• Bjørn Bjorvatn

  Department of Global Public Health and Primary Care, University of Bergen, Norway

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: July 3, 2024
• First Posted: October 24, 2024
• Study Start: August 15, 2023
• Primary Completion: June 30, 2025
• Study Completion: June 30, 2025
• Last Updated: May 1, 2026

Record last verified: 2026-04

Locations

NO (1)