Personalising Children's Screen Use Reduction for Better Sleep, Mental, and Brain Health

NCT05956392 | Recruiting

• 1 other identifier: MEDRES
• Study Type: interventional
• Target: 150
• Locations: 1 country
• Sites: 1

Brief Summary

In Singapore, 64.4% of school-age children sleep less than the minimum recommended duration of 9 hours on school nights, thus risking poor mental, cognitive, and brain health. These short-sleeping children, however, spend on average 2.5 hours per school day on non-academic media use, revealing the potential of reducing their screen time for more sleep. Previous interventions targeted at reducing media use and/or improving sleep among school-age children, though effective in increasing sleep, required cooperation from schools, extensive personnel training, and high commitment of participants, rendering them difficult to implement in Singapore. Existing interventions also focused on evening or pre-bedtime screen use, and took a one-size-fits-all approach, ignoring individual differences in the duration, type, and purpose of media use throughout the day. Here, we propose a scalable approach to curtail media use based on individual need throughout the day. We will conduct a randomised controlled trial during term time, recruiting 150 children, aged 6-12 years, who on school days, sleep less than 8 hours and spend more than 2 hours on media use. At baseline, all participants will record their time use patterns. The research staff will then help the intervention group to repurpose at least 60 minutes of media use per school day for sleep. Importantly, participants can decide the type, timing and duration of media use to curtail, thus giving them a sense of agency and mastery, while boosting their self-efficacy, a vital ingredient in behavioural change. The intervention group will follow this personalised schedule for 2 weeks, while the control group will be in a free-living condition. Two weeks after the intervention has ended, the intervention group will undergo follow-up assessments. Throughout the study, sleep, time use, cognitive functions, and psychological well-being will be assessed daily. Other cognitive tasks and questionnaires will be conducted during 2-3 lab/school-classroom visits, with one-third of the participants also undergoing high-density electroencephalography to measure brain activity.

Conditions

Screen-use Reduction + Sleep Extension; Free-living

Keywords

Cognitive Functions; Neurobehavioural Functions; Sleep Duration; Screen-use; High-density EEG

Outcome Measures

Primary Outcomes (34)

• Change in sustained attention assessed with the Psychomotor Vigilance Task from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Number of attention lapses. More lapses indicate worse performance.

  PVT will be assessed once daily (up to 3 weeks for the control group and up to 4 weeks for the intervention group) using EMA, and again at the end of the baseline, manipulation and follow-up period through a laptop-based test battery.

• Change in sustained attention assessed with the Psychomotor Vigilance Task from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Mean reaction time. Longer mean reaction time indicate worse performance.

  PVT will be assessed once daily (up to 3 weeks for the control group and up to 4 weeks for the intervention group) using EMA, and again at the end of the baseline, manipulation and follow-up period through a laptop-based test battery.

• Change in sustained attention assessed with the Psychomotor Vigilance Task from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Median reaction time. Longer median reaction time indicate worse performance.

  PVT will be assessed once daily (up to 3 weeks for the control group and up to 4 weeks for the intervention group) using EMA, and again at the end of the baseline, manipulation and follow-up period through a laptop-based test battery.

• Change in sustained attention assessed with the Psychomotor Vigilance Task from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Standard deviation in reaction time. Larger standard deviation in reaction time indicate less consistent performance.

  PVT will be assessed once daily (up to 3 weeks for the control group and up to 4 weeks for the intervention group) using EMA, and again at the end of the baseline, manipulation and follow-up period through a laptop-based test battery.

• Change in sustained attention assessed with the Psychomotor Vigilance Task from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Number of commission errors/false starts. More false starts indicate worse performance.

  PVT will be assessed once daily (up to 3 weeks for the control group and up to 4 weeks for the intervention group) using EMA, and again at the end of the baseline, manipulation and follow-up period through a laptop-based test battery.

• Change in number of correct matches assessed with the 1-back task from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Number of correct matches in the 1-back task. More correct matches indicate better performance.

  Once on the last day of the baseline, manipulation and follow-up period through a laptop-based test battery. Up to twice in the control group and up to thrice in intervention group participants.

• Change in number of incorrect matches assessed with the 1-back task from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Number of incorrect matches in the 1-back task. Fewer incorrect matches indicate better performance.

  Once on the last day of the baseline, manipulation and follow-up period through a laptop-based test battery. Up to twice in the control group and up to thrice in intervention group participants.

• Change in number of correct mismatches assessed with the 1-back task from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Number of correct mismatches in the 1-back task. More correct mismatches indicate better performance.

  Once on the last day of the baseline, manipulation and follow-up period through a laptop-based test battery. Up to twice in the control group and up to thrice in intervention group participants.

• Change in number of incorrect mismatches assessed with the 1-back task from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Number of incorrect mismatches in the 1-back task. Fewer incorrect mismatches indicate better performance.

  Once on the last day of the baseline, manipulation and follow-up period through a laptop-based test battery. Up to twice in the control group and up to thrice in intervention group participants.

• Change in discriminability measure (A') assessed with the 1-back task from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Discriminability measure (A')

  Once on the last day of the baseline, manipulation and follow-up period through a laptop-based test battery. Up to twice in the control group and up to thrice in intervention group participants.

• Change in bias measure (B"D) assessed with the 1-back task from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Bias measure (B"D)

  On the last day of the baseline, manipulation and follow-up period through a laptop-based test battery. Up to twice in the control group and up to thrice in intervention group participants.

• Change in number of correct matches assessed with the 2-back task from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Number of correct matches in the 2-back task. More correct matches indicate better performance.

  Once on the last day of the baseline, manipulation and follow-up period through a laptop-based test battery. Up to twice in the control group and up to thrice in intervention group participants.

• Change in number of incorrect matches assessed with the 2-back task from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Number of incorrect matches in the 2-back task. Fewer incorrect matches indicate better performance.

  Once on the last day of the baseline, manipulation and follow-up period through a laptop-based test battery. Up to twice in the control group and up to thrice in intervention group participants.

• Change in number of correct mismatches assessed with the 2-back task from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Number of correct mismatches in the 2-back task. More correct mismatches indicate better performance.

  Once on the last day of the baseline, manipulation and follow-up period through a laptop-based test battery. Up to twice in the control group and up to thrice in intervention group participants.

• Change in number of incorrect mismatches assessed with the 2-back task from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Number of incorrect mismatches in the 2-back task. Fewer incorrect mismatches indicate better performance.

  Once on the last day of the baseline, manipulation and follow-up period through a laptop-based test battery. Up to twice in the control group and up to thrice in intervention group participants.

• Change in discriminability measure (A') assessed with the 2-back task from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Discriminability measure (A')

  Once on the last day of the baseline, manipulation and follow-up period through a laptop-based test battery. Up to twice in the control group and up to thrice in intervention group participants.

• Change in bias measure (B"D) assessed with the 2-back task from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Bias measure (B"D)

  Once on the last day of the baseline, manipulation and follow-up period through a laptop-based test battery. Up to twice in the control group and up to thrice in intervention group participants.

• Change in subjective sleepiness assessed with the Karolinska Sleepiness Scale from baseline to manipulation (for both groups), baseline to follow-up (for intervention group only), and manipulation to follow-up period (for intervention group only)

  Score on the Karolinska Sleepiness Scale (1-9 points). Higher score indicate more sleepiness.

  KSS will be assessed once daily (up to 3 weeks for the control group and up to 4 weeks for the intervention group) using EMA, and again on the last day of the baseline, manipulation and follow-up period through a laptop-based test battery.

• Change in positive mood from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Total score on the positive subscale of the Positive and Negative Affect Schedule for Children(PANAS-C) ranges between 5 and 25. A higher score indicates more positive mood and is considered to be better.

  PANAS-C will be assessed once daily (up to 3 weeks for the control group and up to 4 weeks for the intervention group) using EMA, and again on the last day of the baseline, manipulation and follow-up period through a laptop-based test battery.

• Change in negative mood from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Total score on the negative subscale of the Positive and Negative Affect Schedule for Children(PANAS-C) ranges between 5 and 25. A higher score indicates more negative mood and is considered to be worse.

  PANAS-C will be assessed once daily (up to 3 weeks for the control group and up to 4 weeks for the intervention group) using EMA, and again on the last day of the baseline, manipulation and follow-up period through a laptop-based test battery.

• Change in processing speed assessed with the Symbol Digit Modalities Test from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Number of correct responses in the task

  Once on the last day of the baseline, manipulation and follow-up period through a laptop-based test battery. Up to twice in the control group and up to thrice in intervention group participants.

• Change in digital device use assessed by the Digital Addiction Scale for Children from baseline to manipulation (for both groups), baseline to follow-up (for intervention group only), and manipulation to follow-up period (for intervention group only)

  The Digital Addiction Scale for Children consists of 25 items rated on a five-point Likert scale ranging from 1 (Never) to 5 (Always). A total score is obtained by summing all 25 items (ranging from 25 to 125), with higher scores indicating a higher level of digital addiction.

  Once on the last day of the baseline, manipulation and follow-up period through a laptop-based test battery. Up to twice in the control group and up to thrice in intervention group participants.

• Change in spatial working memory performance assessed by a Dot Memory Task from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Number of correct responses in the task. More correct responses indicate better performance.

  Assessed once daily using EMA in both the control (up to 3 weeks) and intervention (up to 4 weeks) groups. The specific time at which the EMA is attempted daily (within a one hour time frame) is decided based on the participant's choice.

• Change in speed of processing assessed with a Symbol Search Task from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Number of correct responses in the task. More correct responses indicate better performance.

  Assessed once daily using EMA in both the control (up to 3 weeks) and intervention (up to 4 weeks) groups. The specific time at which the EMA is attempted daily (within a one hour time frame) is decided based on the participant's choice.

• Change in speed of processing assessed with a Symbol Search Task from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Median reaction time. Longer median reaction time indicate worse performance.

  Assessed once daily using EMA in both the control (up to 3 weeks) and intervention (up to 4 weeks) groups. The specific time at which the EMA is attempted daily (within a one hour time frame) is decided based on the participant's choice.

• Change in daily screen-use time assessed with time-use diary from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Time spent on electronic devices daily

  Assessed once daily using EMA in both the control (up to 3 weeks) and intervention (up to 4 weeks) groups. The specific time at which the EMA is attempted daily (within a one hour time frame) is decided based on the participant's choice.

• Change in sleep duration from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Time spent sleeping will be assessed through an Actiwatch and the Fitbit worn by the children during the entire course of the study. The time-use app and the sleep diary filled in by parents daily during participation in the study will also help us gain a complete understanding of changes in sleep duration patterns throughout study participation.

  Assessed daily using an actiwatch, fitbit and time-use app/sleep diary. Up to a total of 3 weeks in control participants and up to a total of 4 weeks of daily monitoring in intervention participants.

• Change in sleep efficiency from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Sleep efficiency will be assessed through an actiwatch worn throughout participation in the study.

  Assessed daily using an actiwatch. Up to a total of 3 weeks in control participants and up to a total of 4 weeks of daily monitoring in intervention participants.

• Change in subjective sleepiness ratings by parents and teachers from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Subjective sleepiness will be assessed through the Pediatric Daytime Sleepiness Scale (PDSS) done by the child's parent and teacher. Score will range between 0 and 32 where higher scores indicate more sleepiness.

  Once one the last day of the baseline, manipulation and follow-up period through an online questionnaire sent to parents and teachers. Up to twice in the control group participants and up to thrice in intervention group participants.

• Change in subjective sleepiness ratings by parents and teachers from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Subjective sleepiness will also be assessed through the Karolinska Sleepiness Scale (KSS) done by parents and teachers. The KSS measures subjective sleepiness on a scale of 1='very alert' to 9='very sleepy, fighting sleep. Higher scores indicate more sleepiness.

  Once one the last day of the baseline, manipulation and follow-up period through an online questionnaire sent to parents and teachers. Up to twice in the control group participants and up to thrice in intervention group participants.

• Change in internet addiction symptoms from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Assessed using the Parent-child Internet Addiction Test (PC-IAT) which will indicate the level of problematic behaviour associated with compulsive use of electronic devices

  Once on the last day of the baseline, manipulation and follow-up period through a laptop-based test battery. Up to twice in the control group and up to thrice in intervention group participants.

• Change in internalising and externalising behaviours from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Assessed using the Child Behavioural Checklist done by both parents and teachers.

  Once on the last day of the baseline, manipulation and follow-up period through a laptop-based test battery. Up to twice in the control group and up to thrice in intervention group participants.

• Change in parent-reported sleep behaviours and sleep-related factors from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Assessed using the Singapore Children Sleep Survey done by parents.

  Once on the last day of the baseline, manipulation and follow-up period through a laptop-based test battery. Up to twice in the control group and up to thrice in intervention group participants.

• Change in EEG power and coherence of the prefrontal cortex from baseline to manipulation (for both groups), from baseline to follow-up (for intervention group only), and from manipulation to follow-up period (for intervention group only)

  Assessed using high-density EEG. he natural-logged ratio of theta/beta power for frontal leads will be used in the analyses.

  Once on the last day of the baseline, manipulation and follow-up period through a laptop-based test battery. Up to twice in the control group and up to thrice in intervention group participants.

Study Arms (2)

Screen-use reduction + Sleep extension

EXPERIMENTAL

For the intervention group, participants are required to follow an agreed schedule where one hour of their daily screen-use time during school days will be repurposed for additional sleep during the two-week manipulation period.

Behavioral: Screen-use reduction + Sleep extension

Free-living control

NO INTERVENTION

For the control group, participants will remain under free-living conditions (no restrictions on their screen-use time or sleep time) during the two weeks.

Interventions

Screen-use reduction + Sleep extension BEHAVIORAL

60 minutes of a participants' daily screen-use time on school days will be repurposed for more sleep time.

Screen-use reduction + Sleep extension

Eligibility Criteria

• Age: 6 Years - 12 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17)

You may qualify if:

• Is a Singaporean or Permanent Resident
• Speaks English
• Aged between 6-12 years old
• Habitually sleeps less than 8 hours during school nights
• Habitually spends more than 2 hours on media use (i.e. social media, gaming, and TV / videos) on school days
• Is not on any long-term medications
• Has no known medical or developmental conditions that could affect sleep (e.g. asthma, arthritis, cancer, congenital heart disease, diabetes, epilepsy, eczema, inflammation)
• Has no history of psychiatric or neurological disorders

Sponsors & Collaborators

• National University of Singapore: lead

Study Sites (1)

National University of Singapore

Singapore, 117597, Singapore

RECRUITING

Study Officials

• June Lo, PhD

  National University of Singapore

  PRINCIPAL INVESTIGATOR

Central Study Contacts

June Lo, PhD

CONTACT

+65 66016137; mdclocy@nus.edu.sg

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor

Study Record Dates

• First Submitted: July 4, 2023
• First Posted: July 21, 2023
• Study Start: July 3, 2023
• Primary Completion (Estimated): December 31, 2027
• Study Completion (Estimated): December 31, 2027
• Last Updated: April 13, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share

Locations

SG (1)