Table 4.
Changes in sleep duration, bedtime, wake-up time and sleep quality from before to during the lockdown
| Study | Reported outcome | ||||||
| Measurement tool | Indicator | Before lockdown (Mean (SD)) |
During lockdown (Mean (SD)) |
During lockdown (vs before lockdown) | P value | ||
| Adibelli and Sümen, 2020, Turkey84 | Questionnaire prepared by the research team (increase in sleep time during the pandemic) | % With increased tendency to sleep | 34.2% | ||||
| Aguilar-Farias et al, 2020, Chile39 | Adapted from the questions included in the International Study of Movement Behaviours in the Early Years (SUNRISE), pilot-tested | Sleep duration (hours/day) | 10.92 (1.80) | 11.01 (1.86) | 0.001 | ||
| Sleep quality (Mean score, range: 1–7) | 5.68 (1.54) | 4.93 (1.77) | <0.001 | ||||
| Alonso-Martínez et al, 2021, Spain40 | Wrist-worn GENEActiv tri-axial accelerometer | Sleep duration (hours/day) | 9.51 (0.74) | 9.54 (1.30) | 0.914 | ||
| Sleep efficiency (%) | 84.3% | 82.2% | 0.047 | ||||
| AMHSI, 2020, Multi-country70 | Newly designed sleep-wake patterns questionnaire and daily log adapted from Sleep Diary/Sleep Log of the National Sleep Foundation (NFS, USA) | Sleep duration | 8:36 (1:20) | 9:34 (0:24) | 0.05 | ||
| Araby et al, 2021, Egypt80 | Questionnaire adapted and translated from CDC fact sheet about stressful effects of COVID-19 pandemic on children and teens, 2020 | % With a change of sleep pattern from before to during the lockdown | Change of bedtime | 88.3% | |||
| Difficulty to fall asleep | 49.6% | ||||||
| Wake up afraid and rush to parents | 42.6% | ||||||
| Avoid bedtime | 31.4% | ||||||
| Return to bedwetting | 6.6% | ||||||
| Frequent nightmares | 31.4% | ||||||
| Brzek et al, 2021, Poland43 | Questionnaire related to sleeping behaviours during the pandemic period in comparison to the previous period | Sleep duration per 24 hours (hours) | 9.74 (1.18) | 10.11 (1.21) | <0.001 | ||
| Cacioppo et al, 2020, France85 | Questionnaire developed by a national multidisciplinary group experienced in disability care, pilot-tested | % Reporting increased sleeping difficulties in children during lockdown | 22.0% | ||||
| Cellini et al, 2021, Italy71 | Sleep Disturbance Scale for Children | Time in bed (hours) | 9.37 (0.05) | 10.21 (0.05) | <0.001 | ||
| Bedtime (hour:mm) | 21:30 (0.03) | 22:48 (0.03) | <0.001 | ||||
| Rise time (hour:mm) | 07:11 (0:04) | 09:01 (0:04) | <0.001 | ||||
| Sleep quality (Sleep Disturbance Scale total score; higher scores indicate greater severity of sleep disturbance) | 38.60 (0.58) | 39.90 (0.58) | 0.027 | ||||
| Cerasuolo, 2021, Italy77 | Children’s Sleep Habits Questionnaire (CSHQ) | Bedtime in toddlers and preschoolers (weekdays and weekends) | Delayed | <0.01 | |||
| Rise time in toddlers and preschoolers (weekdays) | Delayed | <0.01 | |||||
| Rise time in toddlers and preschoolers (weekdays) | Delayed | <0.01 | |||||
| Rise time in toddlers and preschoolers (weekends) | No change | ||||||
| CSHQ total score (higher score indicates more disturbed sleep) | Toddlers | 47.51 (8.26) | 46.82 (8.10) | Not significant | |||
| Preschoolers | 51.12 (6.36) | 47.82 (8.08) | 0.020 | ||||
| Cheng et al, 2021, Malaysia88 | Not reported | Sleep duration (hours) | T1DM, Male | 8.07 (1.21) | 9.06 (1.39) | 0.033 | |
| T1DM, Female | 8.18 (1.31) | 9.33 (1.33) | <0.001 | ||||
| T2DM, Male | 7.80 (0.71) | 9.65 (0.94) | 0.001 | ||||
| T2DM, Female | 7.64 (1.12) | 9.55 (1.67) | <0.001 | ||||
| Clarke et al, 2021, UK47 | Topic guide for in-depth interviews to get insights into the perceived impact of lockdown restrictions on preschool children’s physical activity, sedentary behaviour, food intake, and sleep | Children’s sleep quality | Many reported difficulties in getting their child to sleep | ||||
| DiGiorgio et al, 2020, Italy78 | Sleep Disturbance Scale for Children | Sleep Disturbance Scale for Children Score | No change | 0.970 | |||
| Di Giorgio et al, 2021, Italy89 | Ad-hoc created questions about their children’s sleep habits | % Sleeping 8–11 hours per night | 73.0% | 73.0% | |||
| % Often having difficulty falling asleep | 6.0% | 15.0% | 0.001 | ||||
| Dondi et al, 2021, Italy81 | Adapted from the Sleep Disturbance Scale for Children (SDSC) | % Reporting more difficulty in falling asleep during lockdown | 69.3% | ||||
| Garcia et al, 2021, USA91 | Adapted from the National Survey of Children’s Health | Hours of sleep/weekday | 8.72 (1.77) | 9.36 (1.5) | 0.16 | ||
| Hours of sleep/weekend | 9.47 (2.03) | 10 (1.37) | 0.2 | ||||
| Guo et al, 2021, China49 | Change in sleep assessed with the question “Compare with the three months before the outbreak of COVID-19, is there any change in the amount of you (or your child) daily sleeping?” | % Reporting no difference in sleep duration | 47.5% | ||||
| Kaditis et al, 2021, Multi-country75 | Bedtime on weekdays and on weekends | Delayed | <0.01 | ||||
| Wake time on weekdays and on weekends | Delayed | <0.01 | |||||
| Sleep duration on weekdays | Increased | <0.001 | |||||
| Sleep duration on weekends | No change | 0.51 | |||||
| Kahn et al, 2021, USA72 | Objective sleep metrices recorded via videosomnography in the naturalistic home-setting, using Nanit camera monitors | Nighttime sleep duration (Mean difference) | 11.0 min | 0.01 | |||
| Morning rise time (Mean difference) | 9.5 min | 0.008 | |||||
| Lavigne-Cerván et al, 2021, Spain82 | BEARS (Sleep screening tool) | Sleep quality (BEARS Score-screening for sleep disorder) | 7.40 | 13.18 | |||
| Li et al, 2021, China73 | Pittsburgh Sleep Quality Index (PSQI) | Sleep duration (hours/day) | 6.73 (SE 0.05) | 7.18 (SE 0.06) | 0.001 | ||
| Bedtime | 22:57:52 (SE 0:02:05) | 23:22:13 (SE 0:03:02) | 0.001 | ||||
| Wake-up time | 06:45:26 (SE 0:01:54) | 08:05:48 (SE 0:03:08) | 0.001 | ||||
| Sleep quality (score, higher score indicates lower quality) | 6.99 (SE 0.09) | 6.19 (SE 0.09) | <0.001 | ||||
| Lim et al, 2020, Singapore50 | Questionnaire which included information on sleeping patterns of children | Sleep duration (hours/day) | 9.29 (1.00) | 9.63 (1.18) | <0.001 | ||
| Bedtime (hour:mm) | 21:36 (1.02) | 22:05 (1.25) | <0.001 | ||||
| Rise time (hour:mm) | 06:45 (0:58) | 07:49 (0.90) | <0.001 | ||||
| Liu et al, 2020, China74 | Children’s Sleep Habit Questionnaire (CSHQ) | Nocturnal sleep duration (hours/day) | Weekday: 9.47 (0.63) | 10:38 (1.05) | <0.001 | ||
| Weekend: 9.88 (0.78) |
|||||||
| Bedtime (hour:min) | 21:30 (0.03) | 22:48 (0.03) | <0.001 | ||||
| Rise time (hour:min) | 07:11 (0:04) | 09:01 (0:04) | <0.001 | ||||
| Total Children’s Sleep Habits Questionnaire Score (higher score indicates lower sleep quality) | 51.87 (6.77) | 44.28 (6.06) | <0.001 | ||||
| Lokhandwala et al, 2021, USA76 | Actigraphy data together with daily sleep diary (for validation) | 24-hour sleep duration (minutes) | 628.6 (29.4) | 631.6 (30.7) | 0.631 | ||
| Sleep efficiency (%) | 84.9 (4.6) | 85.4 (4.5) | 0.365 | ||||
| López-Bueno et al, 2020, Spain3 | Sleep duration assessed with the question “How many hours does your child usually sleep daily?” | Sleep duration (hours/day) | 9.10 (1.20) | 9.20 (1.60) | 0.129 | ||
| Luijten et al, 2021, Netherlands83 | Patient-Reported Outcome Measurement Information System (PROMIS) scale | PROMIS Sleep Related Impairment Score (higher score indicates greater sleep impairment) | 47.60 (10.00) | 49.90 (8.70) | <0.01 | ||
| Łuszczki et al, 2021, Poland51 | Assessed with the questions "What is the amount of time you sleep during a 24 h period on school days? What is the amount of time you sleep during a 24 h period on weekends? During the past month, how would you rate your sleep quality overall?” | Weekdays sleep duration (hours) | 8.83 (1.64) | 8.55 (1.17) | <0.001 | ||
| Weekends sleep duration (hours) | 10.11 (1.45) | 9.52 (1.36) | <0.001 | ||||
| Sleep quality (Score, higher score indicates better quality) | 1.70 (0.68) | 1.78 (0.65) | 0.032 | ||||
| Masi et al, 2021, Australia92 | Questionnaire developed by the investigators and pilot tested with clinicians, researchers, and a small group of parents | % Reporting reduction in children’s sleep quality | 43.6% | ||||
| Medrano et al, 2021, Spain52 | Sleep time calculated from children’s daily log of wake-up time and bedtime | Weekdays sleep duration (hours/day) | 9.10 (0.90) | 9.90 (1.20) | <0.001 | ||
| Weekend days sleep duration (hours/day) | 9.40 (1.10) | 10.10 (1.60) | <0.001 | ||||
| Mitra et al, 2020, Canada53 | Secondary data (parents reported time spent on various movement behaviours) | % Reporting same sleep duration during lockdown compared to before the lockdown | 51.8% | ||||
| % Reporting same sleep quality | 68.7% | ||||||
| Moore, 2020, Canada27 | Secondary data (change in child’s movement and play behaviours), test-retest (one-week) reliability assessed | Chang in sleep quantity from before to during the lockdown (range: 1–5, 1 = a lot less, 3 = no change, 5 = a lot more) | Children: 3.21 (0.70) | ||||
| Youth: 3.63 (0.84) | |||||||
| Change in sleep quality from before to during the lockdown (range: 1–5, 1 = a lot worse, 3 = no change, 5 = a lot better) | Children: 3.05 (0.66) | ||||||
| Youth: 3.04 (0.73) | |||||||
| Morgül et al, 2020, UK54 | Family daily routines and children’s emotional and behavioural symptoms questionnaire developed by Orgilés et al | Sleep duration (hours/day) | 9.93 (1.45) | 9.55 (1.76) | <0.01 | ||
| Munasinghe et al, 2020, Australia55 | Self-reported 24-hour sleep duration collected via weekly Ecological momentary assessment (EMA) | Median sleep hours (OR) | 1.00 | 1.19 (0.57, 2.51) | |||
| Nathan, 2021, Australia20 | Sleep duration assessed from hours and minutes of sleep reported during the night and the day | Sleep (min/day) | 614.8 (48.5) | 612.8 (67.0) | 0.639 | ||
| Okely et al, 2021, Multi-country26 | Questionnaire developed by the researchers based on the recommendations for each behaviour guideline, tested, and refined as part of SUNRISE pilot study | 24-hour sleep duration (min) | 664.7 (2.9) | 641.2 (3.2) | -9.2 (−28.9, 10.6) | 0.341 | |
| Bedtime (24 hour:min) | 21:20 (0:02) | 22:01 (0:03) | 0:34 (0:14, 0:54)* | 0.003* | |||
| Waketime (24 hour:min) | 7:09 (0:02) | 8:09 (0:03) | 0:59 (0:34, 1:23)* | <0.001* | |||
| % With poor sleep quality | 5.1 (1.0) | 6.0 (0.9) | 0.6 (0.1, 1.5)* | 0.267* | |||
| Pietrobelli et al, 2020, Italy94 | Questionnaire which included question on sleep behaviour | Sleep time (hours/day) | 8.46 (0.85) | 9.11 (1.10) | 0.003 | ||
| Pombo et al, 2021, Portugal56 | Questionnaire developed by the researchers, questions validated by child development experts, and pilot tested | % Spending neither more nor less time on sleep during lockdown | 51.6% | ||||
| Ramos Socarras et al, 2021, Canada79 | Questions derived from the Pittsburgh Sleep Quality Index (PSQI) | Bedtime | Delayed | <0.001 | |||
| Subjective sleep quality | Improved | <0.01 | |||||
| Sá et al, 2021, Brazil58 | Questionnaire created by the research team, elaborated by experts in the field, and tested | % Spending not more or not less time on sleep during lockdown compared to before the lockdown | 47.7% | ||||
| Türkoğlu et al, 2020, Turkey96 | Children’s Sleep Habits Questionnaire (CSHQ) | Total Children’s Sleep Habits Questionnaire Score (higher score indicates lower sleep quality) | 47.82 (7.13) | 50.80 (8.15) | 0.001 | ||
| Yang et al, 2020, China66 | International Physical Activity Questionnaire (IPAQ)-long form | Workdays median sleep duration (hours/day) | 8.00 | 8.10 | <0.001 | ||
| Weekends median sleep duration (hours/day) | 8.50 | 9.00 | <0.001 | ||||
| Zengin et al, 2021, Turkey61 | Questionnaire prepared by the researchers and reviewed by specialists | % With an increased sleep time | 46.4% | ||||
| % Sleeping late | 56.8% | ||||||
| % Getting up late | 39.0% | ||||||
*Adjusted.
T1DM, type 1 diabetes mellitus.