Table 1.
Student and school demographics and sleep, behavioral health, and academic performance outcomes.
| Author, Year, Country | Type of School | Sample (mean age, age range, percent girls, percent students of color) | Total Sleep Time (TST) | Sleep Measure | Duration | Efficiency | Timing | Alertness and Sleepiness | Satisfaction/Quality | Behavioral Health | Academic |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Lufi et al, 201127 Israel | Public (8th-graders) | N = 47, Mage = 13.78 (SD = 0.28), 57% girls | Experimental: 8 hours, 26 min. (week 1) and 7 hours, 31 min. (week 2) Control: 7 hours and 29 min. (week 1) and 7 hours, 18 min. (week 2) | Actigraphy and daily sleep logs for 5-day period | ✓ | ✓ | ✓ | Executive function (MATH-CPT, d2 Task of Inattention) | |||
| Owens et al,17 2017 USA | 10th largest US school district; 19 public schools (3 secondary, 8 middle schools) | N = 1,051, Mage = 13.5 (SD = 0.60), 54.6% girls, 44.1% students of color, 64% FRL | Before SST advance: 8 hours and 25 min.; after SST advance: 8 hours and 9 min. | SSHS, Sleepiness subscale | ✓ | ✓ | ✓ | ✓ | |||
| Temkin et al,25 2018 USA | 8 middle schools (7th/8th grade) and 3 secondary school (7th–12th grade) from a “diverse suburban school district” | N = 973, age range 12–15, 51% girls, 38% students of color, 5% FRL | Early SST: 8.15 hours, later SST: 8.39 hours | School Sleep Habits Survey, Sleepiness subscale; PSQI | ✓ | ✓ | ✓ | ||||
| Lo et al, 201828 Singapore | All-girls’ secondary school (7th–12th) | N = 375, Mag = 14.6 (SD = 1.15), 1-month f/up (n = 352), 9-month f/up (n = 150) | 1-month: 2.06 min. increase, 9-month: 9.95 min. increase; both time points: average TST was 5 hours and 48 min. | Actigraphy, daily sleep logs; Karolinska Sleepiness Scale | ✓ | ✓ | ✓ | PANAS-X | |||
| Das-Friebel et al,30 2020 Switzerland | 3 Lower-track secondary schools (8th–9th grade) | School Start Time Change group (n = 249), Mage = 14.82 (.54), 41.8% female; comparison group (n = 414), Mage=14.97 [.60], 47.3% female | T1: 8 hours, 10 min. T2: 8 hours, 2 min. | Student school satisfaction survey | ✓ | ✓ | ✓ | ||||
| Wolfson et al,24 2007 USA | Urban public | N = 205, 7th (n = 99), 8th-graders (n = 106), 60% girls, 18% FRL, 40% students of color (school L), 54% students of color (school E) | School L Fall: 8.90 hours, Spring: 8.92 hours; school E Fall: 8.28 hours, Spring 7.83 hours | SSHS, Sleepiness and Sleep-Wake Behavior Problems subscales | ✓ | ✓ | ✓ | Attendance and tardiness records | Fall term GPA (100-point scale) | ||
| Kim et al, 201929 Korea | Public | N = 238, Mage = 13.5(SD = 0.5), range 13–14, 54.62% girls | Increase TST: 2-month: 7.4 hours; 12-month: 8.0 hours; decrease TST: 2-month 8.1 hours, 12-month: 7.3 hours | PSQI; SSHS, Sleepiness and Sleep/Wake Problem Behavior subscale | ✓ | ✓ | ✓ | ✓ | ✓ | PANAS-X, Depressed Mood subscale, self-reported tardiness | |
| Lewin et al, 201726 United States | 26 “demographically diverse school districts” | N = 6,936 (Year 2008), n = 11,991 (Year 2010), n = 10,768 (Year 2012), 58.2% students of color, 50.2% girls, 58% of schools ranged from 25%–75% eligibility for FRL | Earliest: less likely to report less than 8 hours of TST compared to “latest” | Weeknight sleep duration (< 7 hours, 7 hours, 8 hours, or > 9 hours) | ✓ | Self-reported grades and academic effort | |||||
| Whitaker et al,18 2019 United States | 10th largest US school district, 19 public schools (3 secondary, 8 middle schools) | N = 1,051, 7th- and 8th-grade students, Mage = 13.5 (SD = 0.60) years, 54.6% girls, 44.1% students of color, 64% FRL | Before SST advance: 8 hours and 25 min. After SST advance: 8 hours and 9 min. | Executive function (BRIEF), self-reported injury, physical activity, and BMI | |||||||
| Edwards, 201220 USA | 16th largest district, mostly urban/suburban | Did not report | End-of-grade test scores |
✓ = measured outcome, BMI = body mass index, FRL = free/reduced lunch, Mage = median age, MATH-CPT = Mathematics Continuous Performance Test, PANAS = Positive and Negative Affect Schedule, PSQI = Pittsburgh Subjective Sleep Quality Index, SD = standard deviation, SST = school start time, TST = total sleep time.