Evidence-Based Question: Sleep

Source A

Introduction
Researchers investigated the effects of changes in school start times on students in elementary, middle, and
high school. They were particularly interested in how school start times related to factors such as academic
performance and sleep.

Participants
Eight school districts in Minnesota, and a total of 38,019 students, were involved in this study. Most of the
students were white (54.7%), with 12.4% Hispanic, 8.8% Black, 8.6% Asian, 4.9% multiracial, 3.6% Somali,
3.1% American Indian, and 2.1% Hmong 2%. The sample consisted of 49.2% women and 50.8% men. The grade
levels of students were evenly divided (i.e., 25.6% grade 5, 27.3% grade 8, 26.1% grade 9, and 20.9%
grade 11).

Method
Four of the school districts observed shifted to a later school start time, and the four other districts kept an
earlier school start time. Two variables were measured in this study. The first was the grade point average
(GPA) of the students. Students reported the course grades they generally received during their current school
year (e.g., Mostly As, Mostly Bs, etc.). The responses were converted to values on a 4.0 scale (mean = 3.2,
standard deviation = 0.9). The second measured variable was the amount of sleep students generally got on a
school night and whether they met the recommended hours of sleep for their grade level.

Results and Discussion
Results showed that students in school districts that moved to a later start time reported higher GPAs and that
higher proportions of those students reported obtaining the recommended hours of sleep as compared with
students in districts with the earlier school start time. The increase in GPA for each grade in the districts with a
later school start time (that is, comparing grade 5, grade 8, grade 9, and grade 11) over the districts with the
earlier school start time ranged from 0.07 to 0.13 GPA points.
The probability of meeting the recommended hours of sleep increased by 16% for students in districts with a
later school start time, a statistically significant finding. However, for students in districts with a later school
start time, the likelihood of students obtaining the recommended hours of sleep increased by 35% in grade 5,
11% in grade 8, 8% in grade 9, and 5% in grade 11. Only the grade 8 increase was statistically significant. The
likelihood of obtaining the recommended hours of sleep for students in districts with an early school start time
did not change at statistically significant levels.

Source B

Introduction

Most adolescents in the United States do not obtain sufficient sleep. Early school start times play a significant
role in adolescent sleep deprivation. Most primary and secondary schools begin classes earlier than 8:30 am.
Perceived barriers to implementing a delayed school start time have been suggested in the literature but have
not been measured. This study explored both the potential barriers to implementing later high school start
times, and other, facilitating factors that may encourage adoption of this practice.

Participants

A convenience sample of 116 respondents participated in the survey, with a response rate of 7.2%. The
participants' job titles included superintendents (7.8%; 9 participants), assistant superintendents (16.4%; 19
participants), principals (20.7%; 24 participants), assistant principals (42.2%; 40 participants), counselors (11.2%, 13 participants), and school board members (1.7%; 2 participants). At the time of this study (2017), all worked in a high school that was identified as having implemented a delayed school start time.

Method

School administrators who had delayed their school start times were invited to complete an online
questionnaire ranking the perceived barriers and facilitating factors for implementing the delayed start times.
Participants were asked if they considered each barrier question as "significant," "moderate," "minor barrier," or
"not a barrier" to interfere with implementing a delayed school start time. These statements referred to
transportation issues, extracurricular considerations, stakeholder groups who were resistant to change, and
additional factors such as time for homework and amount of time waiting for the bus.
Participants were also asked if each facilitating factor statement was "significant," "moderate," "minor," or "not a
facilitating factor" to support implementing a delayed school start time. These statements addressed
stakeholder involvement and education, scheduling alternatives, transportation, and other
factors, such as spending less unsupervised time at home.

Results

The questionnaire contained the following open-response questions:
•"Do you offer classes that students can elect to take before the delayed school start time (sometimes
called "zero-hour classes)?"
•"Did your district 'flip' elementary and high school start times?"
•"Would you recommend that other districts pursue delaying a school start time?"

Distribution of Top 10 Perceived Barriers for School Start Time Delay
Barrier -------------------------------------------------------------------------------------------------Barrier Percentage
Athletes missing more afternoon classes to attend or travel to games -----------------------84.2
Less time after school for athletic activities ---------------------------------------------------------80.7
Family members resistant to change schedule -----------------------------------------------------78.9
Unavailability of adolescents to provide after-school care for siblings -----------------------75.6
Teachers resistant to change schedule ----------------------------------------------------------------74.8
Use of a tiered school bus transportation system --------------------------------------------------71.1
Elementary students having to wait for bus pickup in the early morning --------------------69.6
Less time for adolescents to work ----------------------------------------------------------------------65.8
Student resistant to changing their schedule --------------------------------------------------------63.5
Increased school transportation costs -----------------------------------------------------------------58.4

Distribution of Top 10 Facilitating Factors for School Start Time Change
Facilitating Factor -----------------------------------------------------------------------------Facilitating Factor Percentage
Involvement of the teachers in the decision-making process -------------------------------------------84.5
Involvement of the school administrators in the decision- making process -------------------------84.4
Providing education on adolescent sleep patterns—for students --------------------------------------83.5
Providing education on adolescent sleep patterns—for family members ----------------------------82.5
Providing education on adolescent sleep patterns—for teachers --------------------------------------81.5
Involvement of the family members in the decision-making process ---------------------------------80.9
Involvement of students in the decision-making process ------------------------------------------------79.1
Providing education on adolescent sleep patterns—for school administrators --------------------77.1
Ability to schedule elementary start times to maintain bus tier system ------------------------------74.5
Involvement of support staff in the decision-making process ------------------------------------------70.4

Source C

Introduction

The American Academy of Pediatrics developed the following statement on school start times. A committee of
scientists and practitioners who specialize in pediatric health issues intended the statement to offer advice on
best practices for school start times.

Statement
The American Academy of Pediatrics recognizes that insufficient sleep is an important issue for adolescents.
While several factors may influence students' ability to get enough sleep, evidence strongly suggests that
earlier school start times contribute to sleep deprivation. The American Academy of Pediatrics strongly supports efforts to set school start times for middle and high school students in a way that helps them get 8.5 to 9.5 hours of sleep a night to improve physical and mental health, safety, academic performance, and quality of life.
Biologically, most adolescents experience a "phase delay" in their sleep-wake cycle when they start going
through puberty. As compared to their middle childhood sleep- wake cycle, adolescents experience a shift of
up to 2 hours in their sleep-wake cycle, which means they fall asleep later. Insufficient sleep hurts academic performance.

One study found that 28% of students reported falling asleep in school at least once a week, and more than 1 in 5 students fell asleep doing homework at least once a week. Many studies show an association between decreased sleep duration and lower academic achievement, as well as higher rates of absenteeism and tardiness and decreased readiness to learn. An increase in anxiety and mood disorders in adolescents has also been linked to poor quality and deprivation of sleep. Other specific health-related effects of sleep loss include increased use of stimulants
(e.g., caffeine, prescription medications) to counter the effects of chronic sleepiness on academic
performance. Adolescents are also at greater risk of drowsy driving-related crashes because of sleep
deprivation. According to the US Department of Education statistics for 2011-2012, approximately 43% of the over 18,000 public high schools in the United States currently have a start time before 8:00 AM. The ongoing debate among school districts in the United States regarding later start times for middle and high schools continues to spark controversy. Perceived barriers to changing school schedules include shorter time for athletic practices and interference with scheduling of games, reduced after-school employment hours for students, challenges in providing child care for younger siblings, adjustments in parent and family schedules, potential safety issues, effects on sleep
duration in younger children if elementary school schedules are "flipped" with those of middle/high school
students, and the need to make alternative transportation arrangements.
Adapted from American Academy of Pediatrics.