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Trial registered on ANZCTR


Registration number
ACTRN12624000206527
Ethics application status
Approved
Date submitted
31/01/2024
Date registered
1/03/2024
Date last updated
23/06/2024
Date data sharing statement initially provided
1/03/2024
Type of registration
Prospectively registered

Titles & IDs
Public title
The Helpful Activities Before It is Time for Bed (HABITS) Study: The effect of food, physical activity and screen time on sleep in children
Scientific title
The effect of food, physical activity and screen time on sleep in children: the HABITS randomised crossover trial
Secondary ID [1] 311426 0
Nil known
Universal Trial Number (UTN)
Not applicable
Trial acronym
HABITS
Linked study record
Not applicable

Health condition
Health condition(s) or problem(s) studied:
Sleep 332715 0
Condition category
Condition code
Mental Health 329428 329428 0 0
Studies of normal psychology, cognitive function and behaviour

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Advisory groups worldwide endorse a range of behaviours, collectively known as ‘sleep hygiene’, which are thought to promote good sleep health. These behaviours include sleep habits, environments (e.g. bedding, temperature and noise), and pre-bed behaviours. However, the evidence base illustrating that each of these strategies actually influences sleep in children is poor, particularly those recommendations focusing on restricting the use of electronic media, vigorous exercise, or the consumption of food in the hour before bed.

HABITS is a randomised crossover trial that will investigate whether undertaking these behaviours influences sleep that night. Following a baseline week to measure 'usual' sleep (bedtime, sleep duration and sleep quality), participants will be randomised to the order in which they complete four conditions over four weeks.
Condition 1 (No week - the comparison or ideal week): Avoid screen use and physical activity and do not have any food in the hour before bed.
Condition 2 (Screens week): Use screens for at least 30 minutes in the hour before bed (but restrict physical activity and do not have any food). In this context, screens include television, computers, phones, tablets, gaming consoles and all other digital devices.
Condition 3 (Exercise week): Be physically active for at least 30 minutes in the hour before bed (but restrict screens and do not have any food). In this context, physically active refers to moderate to vigorous PA. Predicted max heart rate (HR) will be estimated using the Tanaka equation (MHR = 208–0.7*age) https://www.tandfonline.com/doi/full/10.1080/02701367.2019.1615605) and participants will be asked to aim for the CDC recommended % HR values for moderate activity (65% predicted Max HR) as the minimum level to target during the exercise intervention. This will go alongside video footage that will confirm that the participants engaged in PA.
Condition 4 (Eat dinner week): Eat dinner in the hour before bed (but restrict screens and physical activity). No minimum number of calories will not be set; however a trained dietitian will assess the participants usual “meal time” food intake collected at the baseline appointment, and make recommendations to the family around how much food would be considered acceptable. Participants will be able to move their dinner meal into the hour before bed, and if this is not possible, the researchers will give the participant and the caregiver a list of options that would an appropriate amount of food, to ensure adherence.

Families will be asked to follow each intervention condition on the same consecutive three days of each intervention week (days 5-7). These 3 days will provide enough data to determine how each behaviour influences sleep, while allowing a washout between each condition (in case the behaviours do impact sleep) and limiting participant burden. As we are examining the effect of the condition on sleep the same night, this amounts to three observations per participant per condition, which should give more reliable estimates than just one observation per condition. Each family can choose what days of the week are days 5-7 for them, as long as the same days apply across all five weeks. All interventions will occur during the school term to limit known changes in sleep caused by holidays and the time around daylight savings will be avoided. Information and details about the interventions will be delivered by trained researchers, through face-to-face appointments at the participant's home, but parents will play a role in administering the interventions as well.

Adherence to each intervention condition (on days 5-7 of each experimental week) will be measured using wearable video cameras from 90 minutes before usual bedtime until the child goes to bed. The cameras go on 90 mins before and not 60 mins in order to account for potential variation in actual bedtime relative to usual bedtime. These cameras are worn on chest harnesses, facing outwards and capture what activities the child is engaging in. Video footage will be analysed to measure adherence as follows:
Condition 1: Children use screens and engage in physical activity for less than or equal to 5 mins and do not consume food in the hour before bed.
Condition 2: Children spend at least 30 mins on screens in the hour before bed (and engage in physical activity for less than or equal to 5 mins and do not consume food).
Condition 3: Children spend at least 30 mins being physically active in the hour before bed (and use screens for less than or equal to 5 mins and do not consume food).
Condition 4: Children consume their dinner meal in the hour before bed (and use screens and engage in physical activity for less than or equal to 5 mins).

Sleep will be measured using waist-worn accelerometers at baseline and during each intervention week. Sleep latency will be measured using a second video camera placed in a tripod in the child's bedroom. This camera will capture when the child goes to bed, stops using any props (e.g. books) and attempts to go to sleep.
Intervention code [1] 327872 0
Lifestyle
Comparator / control treatment
As this a cross-over design, there are four active conditions (no, screens, activity and dinner weeks as above) and no control condition per se. Baseline measures are collected in week 1 but these are used to: (a) describe the sample, (b) determine their usual sleeping patterns including bedtime, and (c) familiarise participants with the equipment. The main analyses compare outcomes between conditions 1 to 4 and do not include the baseline measures.
Control group
Active

Outcomes
Primary outcome [1] 337248 0
Total sleep time (minutes)
Timepoint [1] 337248 0
Days 5-7 of intervention weeks 1 to 4
Primary outcome [2] 337249 0
Sleep disturbances
Timepoint [2] 337249 0
Days 6-8 of intervention weeks 1 to 4
Secondary outcome [1] 431201 0
Sleep latency
Timepoint [1] 431201 0
Days 5-7 of intervention weeks 1 to 4
Secondary outcome [2] 431202 0
Wellbeing
Timepoint [2] 431202 0
Day 8 of intervention weeks 1 to 4

Eligibility
Key inclusion criteria
• Aged 10-15 years
• Live within a 30km radius of Dunedin City
Minimum age
10 Years
Maximum age
15 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
• Have been diagnosed with a sleep disorder or a chronic medical condition that would affect the child completing the intervention
• Are currently under treatment for a sleep disorder.
• Taking any medications that influence sleep

Study design
Purpose of the study
Prevention
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
YES, the person determining who is eligible is unaware at the time of inclusion of group allocation. Allocation is done by central randomisation by computer.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation using a randomisation table created by computer software
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?


The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
To detect a difference of 15 minutes in sleep duration (primary outcome), using a within-person SD of 35 minutes with 90% power to the 0.05 alpha level, a sample size of 60 would be needed. This would also be sufficient to detect a 0.45 SD difference in subjective sleep quality (PROMIS sleep disturbance daily scale, secondary outcome 1). We will recruit 72 children, allowing for 20% non-adherence, drop-out or incomplete data.
Participants will be randomised to the order in which they will carry out the interventions after the baseline week assessments. There are four different orders possible, determined from a Williams design Latin square that is balanced for first order carry over effects. A randomisation schedule will be created by the study biostatistician using Stata 17.0 (StataCorp, TX) with stratification by age group (10-12/13-15 years) and random sized blocks. This will be uploaded to the REDCap randomisation module.
As this is a mechanistic trial aimed at testing the efficacy of the different conditions, primary statistical analyses will be undertaken using data from adherent days; secondary analyses will use all data. Mixed effects regression models with a random effect for participant will be used to estimate mean differences, 95% confidence intervals (CI), and p-values for conditions 2, 3, and 4 compared with condition 1. Residuals will be plotted and visually assessed for homoskedasticity and normality. Results will be reported in line with the CONSORT statement extension to crossover trials.

Recruitment
Recruitment status
Recruiting
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment outside Australia
Country [1] 26122 0
New Zealand
State/province [1] 26122 0

Funding & Sponsors
Funding source category [1] 315699 0
Government body
Name [1] 315699 0
Health Research Council of New Zealand
Country [1] 315699 0
New Zealand
Funding source category [2] 315700 0
Charities/Societies/Foundations
Name [2] 315700 0
Lotteries Health Research
Country [2] 315700 0
New Zealand
Primary sponsor type
University
Name
University of Otago
Address
Country
New Zealand
Secondary sponsor category [1] 317804 0
None
Name [1] 317804 0
Address [1] 317804 0
Country [1] 317804 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 314567 0
University of Otago Human Ethics Committee (Health)
Ethics committee address [1] 314567 0
Ethics committee country [1] 314567 0
New Zealand
Date submitted for ethics approval [1] 314567 0
13/03/2023
Approval date [1] 314567 0
27/03/2023
Ethics approval number [1] 314567 0
H23/039

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 132038 0
Prof Rachael Taylor
Address 132038 0
Department of Medicine, University of Otago, PO Box 56, Dunedin 9010
Country 132038 0
New Zealand
Phone 132038 0
+64 21 479 559
Fax 132038 0
Email 132038 0
Contact person for public queries
Name 132039 0
Rachael Taylor
Address 132039 0
Department of Medicine, University of Otago, PO Box 56, Dunedin 9010
Country 132039 0
New Zealand
Phone 132039 0
+64 21 479 559
Fax 132039 0
Email 132039 0
Contact person for scientific queries
Name 132040 0
Rachael Taylor
Address 132040 0
Department of Medicine, University of Otago, PO Box 56, Dunedin 9010
Country 132040 0
New Zealand
Phone 132040 0
+64 21 479 559
Fax 132040 0
Email 132040 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
Yes
What data in particular will be shared?
All data except for the video footage (as participants might be identifiable) once it has been de-identified. However, the coded information arising from the video footage (adherence to the intervention protocols) will be made available.
When will data be available (start and end dates)?
Data will be made available from 6 months following publication of the main outcomes for a two-year period.
Available to whom?
Researchers who provide a methodologically sound proposal on a case-by-case basis at the
discretion of the Principal Investigator.
Available for what types of analyses?
Any reasonable request on a case-by-case basis at the discretion of the Principal Investigator.
How or where can data be obtained?
From the principal investigator at [email protected].


What supporting documents are/will be available?

Doc. No.TypeCitationLinkEmailOther DetailsAttachment
21516Study protocol  [email protected]
21517Data dictionary  [email protected]



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.