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Is 8:30 a.m. still too early to start school? A 10:00 a.m. school start time improves health and performance of students aged 13-16

Kelley, P., Lockley, S.W., Kelley, J. and Evans, M.D.R. (2017) Is 8:30 a.m. still too early to start school? A 10:00 a.m. school start time improves health and performance of students aged 13-16 Frontiers in Human Neuroscience, 11.

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While many studies have shown the benefits of later school starts, including better student attendance, higher test scores, and improved sleep duration, few have used starting times later than 9:00 a.m. Here we report on the implementation and impact of a 10 a.m. school start time for 13 to 16-year-old students. A 4-year observational study using a before-after-before (A-B-A) design was carried out in an English statefunded high school. School start times were changed from 8:50 a.m. in study year 0, to 10 a.m. in years 1-2, and then back to 8:50 a.m. in year 3. Measures of student health (absence due to illness) and academic performance (national examination results) were used for all students. Implementing a 10 a.m. start saw a decrease in student illness after 2 years of over 50% (p < 0.0005 and effect size: Cohen�s d = 1.07), and reverting to an 8:50 a.m. start reversed this improvement, leading to an increase of 30% in student illness (p < 0.0005 and Cohen�s d = 0.47). The 10:00 a.m. start was associated with a 12% increase in the value-added number of students making good academic progress (in standard national examinations) that was significant (<0.0005) and equivalent to 20% of the national benchmark. These results show that changing to a 10:00 a.m. high school start time can greatly reduce illness and improve academic performance. Implementing school start times later than 8:30 a.m., which may address the circadian delay in adolescents� sleep rhythms more effectively for evening chronotypes, appears to have few costs and substantial benefits. © 2017 Kelley, Lockley, Kelley and Evans.

Item Type: Article
Authors :
Kelley, P.
Kelley, J.
Evans, M.D.R.
Date : 2017
DOI : 10.3389/fnhum.2017.00588
Uncontrolled Keywords : Academic performance, Adolescence, Circadian, Circadian social science, Illness, School start times, Sleep, academic achievement, adolescence, adolescent, article, effect size, female, high school, human, male, observational study, sleep pattern, sociology, student
Depositing User : Clive Harris
Date Deposited : 17 Jun 2020 00:52
Last Modified : 17 Jun 2020 00:52

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