Abstract
Objectives
High school start times are a key contributor to insufficient sleep. This study investigated
associations of high school start times with bedtime, wake time, and time in bed among
urban teenagers.
Design
Daily-diary study nested within the prospective Fragile Families and Child Wellbeing
Study.
Setting
Twenty US cities.
Participants
Four hundred thirteen teenagers who completed ≥1 daily diary report on a school day.
Measurements
Participating teens were asked to complete daily diaries for 7 consecutive days. School-day
daily diaries (3.8 ± 1.6 entries per person) were used in analyses (N = 1555 school days). High school start time, the main predictor, was categorized as
7:00-7:29 am (15%), 7:30-7:59 am (22%), 8:00-8:29 am (35%), and 8:30 am or later (28%). Multilevel modeling examined the associations of school start times
with bedtime, wake time, and time in bed. Models adjusted for age, sex, race/ethnicity,
household income, caregiver's education, and school type.
Results
Teens with the earliest high school start times (7:00-7:29 am) obtained 46 minutes less time in bed on average compared with teens with high school
start times at 8:30 am or later (P < .001). Teens exhibited a dose-response relationship between earlier school start times
and shorter time in bed, primarily due to earlier wake times (P < .05). Start times after 8:30 am were associated with increased time in bed, extending morning sleep by 27-57 minutes
(P < .05) when compared with teens with earlier school start times.
Conclusion
Later school start times are associated with later wake times in our large, diverse
sample. Teens starting school at 8:30 am or later are the only group with an average time in bed permitting 8 hours of sleep,
the minimum recommended by expert consensus for health and well-being.
Keywords
To read this article in full you will need to make a payment
Purchase one-time access:
Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online accessOne-time access price info
- For academic or personal research use, select 'Academic and Personal'
- For corporate R&D use, select 'Corporate R&D Professionals'
Subscribe:
Subscribe to Sleep Health: Journal of the National Sleep FoundationAlready a print subscriber? Claim online access
Already an online subscriber? Sign in
Register: Create an account
Institutional Access: Sign in to ScienceDirect
References
- Youth risk behavior surveillance—United States, 2015.MMWR Surveill Summ. 2016; 65: 1-174
- Recommended amount of sleep for pediatric populations: a consensus statement of the American Academy of Sleep Medicine.J Clin Sleep Med. 2016; 12: 785-786
- National Sleep Foundation's sleep time duration recommendations: methodology and results summary.Sleep Health. 2015; 1: 40-43
- Regulation of adolescent sleep: implications for behavior.Ann N Y Acad Sci. 2004; 1021: 276-291
- An approach to studying circadian rhythms of adolescent humans.J Biol Rhythms. 1997; 12: 278-289
- Association between puberty and delayed phase preference.Sleep. 1993; 16: 258-262
- Sleep, circadian rhythms, and delayed phase in adolescence.Sleep Med. 2007; 8: 602-612
- Impact of delaying school start time on adolescent sleep, mood, and behavior.Arch Pediatr Adolesc Med. 2010; 164: 608-614
- The effects of sleep restriction and extension on school-age children: what a difference an hour makes.Child Dev. 2003; 74: 444-455
- Sleep and student performance at school.J Sch Health. 2005; 75: 248-254
- Sleep, learning, and the developing brain: early-to-bed as a healthy and wise choice for school aged children.Sleep. 2005; 28: 1498-1499
- Sleep duration and injury-related risk behaviors among high school students—United States, 2007-2013.MMWR Morb Mortal Wkly Rep. 2016; 65: 337-341
- Adolescent sleep, school start times, and teen motor vehicle crashes.J Clin Sleep Med. 2008; 4: 533-535
- School Start Times for Adolescents.Pediatrics. 2014; 134: 642-649
- Fragile families: sample and design.Child Youth Serv Rev. 2001; 23: 303-326
- Who Has time to sleep?.J Public Health (Oxf). 2005; 27: 205-211
- Short sleep duration across income, education, and race/ethnic groups: population prevalence and growing disparities during 34 years of follow-up.Ann Epidemiol. 2007; 17: 948-955
- School start time and adolescent sleep patterns: results from the U.S. National Comorbidity Survey—adolescent supplement.Am J Public Health. 2015; 105: 1351-1357
- Sociodemographic and behavioral predictors of bed time and wake time among US adolescents aged 15 to 17 Years.J Pediatr. 2008;
- Setting adolescents up for success: promoting a policy to delay high school start times.J Sch Health. 2016; 86: 552-557
- The impact of school daily schedule on adolescent Sleep.Pediatrics. 2005; 115: 1555-1561
- Estimating dim light melatonin onset (Dlmo) phase in adolescents using summer or school-year sleep/wake schedules.Sleep. 2006; 29: 1632-1641
- Sleep deficiency on school days in Icelandic youth, as assessed by wrist accelerometry.Sleep Med. 2017; 33: 103-108
- Extended nights, sleep loss, and recovery sleep in adolescents.Arch Ital Biol. 2001; 139: 301-312
- The relationships between sex, age, geography and time in bed in adolescents: a meta-analysis of data from 23 countries.Sleep Med Rev. 2010; 14: 371-378
- Delaying school starting time by one hour: some effects on attention levels in adolescents.J Clin Sleep Med. 2011; 7: 137-143
- School start times for middle school and high school students—United States, 2011-12 school year.MMWR Morb Mortal Wkly Rep. 2015; 64: 809-813
- Regulation of sleepiness in adolescents: update, insights, and speculation.Sleep. 2002; 25: 453-460
- Single-parent family structure and sleep problems in black and white adolescents.Sleep Med. 2014; 15: 255-261
- Diary methods: capturing life as it is lived.Annu Rev Psychol. 2003; 54: 579-616
- Daily diary design.in: Whitbourne S.K. Encyclopedia of Adulthood and Aging. Wiley-Blackwell, Oxford, UK2016: 297-300
- Sleep questionnaire versus sleep diary: which measure is Better?.Int J Rehab Health. 2000; 5: 205-209
- Examining the Impact of Later School Start Times on the Health and Academic Performance of High School Students: A Multi-Site Study.University of Minnesota, St. Paul, MN2014
- Sleepless in Fairfax: the difference one more hour of sleep can make for teen hopelessness, suicidal ideation, and substance use.J Youth Adolesc. 2015; 44: 362-378
- Recent updates in the social and environmental determinants of sleep health.Curr Sleep Med Rep. 2015; 1: 212-217
- Social and demographic predictors of preschoolers' bedtime routines.J Dev Behav Pediatr. 2009; 30: 394-402
- Common method biases in behavioral research: a critical review of the literature and recommended remedies.J Appl Psychol. 2003; 88: 879-903
Article info
Publication history
Published online: October 16, 2017
Accepted:
September 9,
2017
Received in revised form:
August 20,
2017
Received:
June 23,
2017
Identification
Copyright
© 2017 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.