Impact of weighted blankets on sleep disturbance among children with attention deficit hyperactivity disorders (ADHD): study protocol for a pragmatic randomised controlled trial

Abstract

Introduction

Sleep disturbances are common among children with attention deficit hyperactivity disorder (ADHD) and may affect well-being. Weighted blankets have been proposed to reduce restlessness via sensory integration by stimulating the tactile and proprioceptive senses. Evidence for an effect on sleep and functional impairment is however sparse. We here describe a trial which aims to compare the effect of using a weighted blanket relative to a non-weighted sham blanket on total sleep time in children with ADHD.

Methods

A parallel group randomised controlled trial will be conducted. We anticipate enrolling 340 patients from six public and one private child and adolescent mental health centres in the Capital Region of Denmark. Patients are aged 5 to 12 years, diagnosed with ADHD or attention deficit disorders (ADD) according. Patients will be randomly allocated (1:1) to either a weighted or non-weighted blanket as add-on to usual treatment. The allocation sequence will be stratified by age (5–8 years vs. 9–12 years), ADHD medication (yes vs. no) and use of sleep medication (yes vs. no). Patients in both groups will be guided in using the weighted- or non-weighted blanket every night and at least once daily for four weeks. The primary outcome will be change from baseline to end of trial 4 weeks from baseline in average total night sleep time, assessed with sleep actigraphy. Secondary outcomes are child functioning impairment, sleep onset latency, number of awakenings, sleep efficiency, ADHD core symptoms, quality of life, and parental quality of life and stress. Main analyses for the efficacy outcomes will be assessed using intention-to-treat analysis. All results from statistical analyses on key secondary endpoints will be accompanied by two-sided 95% CIs and corresponding p values.

Discussion

The implication of this trial holds the potential to have substantial impact on clinical practices and health policy. The research findings could establish an evidence-based, non-pharmacological approach for children with ADHD and sleep problems.

Trial registration

The study protocol is registered on ClinicalTrials.gov no. NCT06194162. Registered on January 8, 2024. Protocol version: Version 1.0.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12888-025-06768-6.

Introduction

Attention Deficit Hyperactivity Disorder (ADHD) is one of the most frequent neurodevelopmental disorders in childhood and adolescence [1]. A recent umbrella review on systematic reviews showed that the global prevalence of ADHD in children and adolescents was 8.0% (95%CI 6.0–10%). The prevalence was twice as high in boys (10%) compared to girls (5%) [1]. It is estimated that approximately 3–5% of Danish children and adolescents are diagnosed with ADHD [2]. Children with ADHD typically have difficulties retaining attention, are often hyperactive, and act impulsively [3]. The disorder interferes with both development and daily functioning, it often persists into adulthood and affects social relationships as well as academic and work performance [4–6]. The majority of children and adolescents with ADHD have comorbid disorders [7, 8] with evidence showing that sleep disturbances are very common among school children with ADHD, affecting nearly three-quarters [9]. Sleep disturbances include difficulties initiating sleep (such as delayed onset sleep or bedtime resistance) and maintaining sleep (frequent nocturnal awakenings or restlessness), but also affect tiredness on waking, daytime sleepiness, and risk of nightmares [9]. Sleep disturbances among children with ADHD affect the overall wellbeing of the family, leading to poorer parental mental health and higher stress among family members [10].

Sensory processing is the ability to detect, modulate, interpret and organize incoming sensory information [11] and research indicate that sensory processing is impaired among children with ADHD [12]. In line with this, a cross-sectional study conducted among 72 children aged 6 to 14 years showed that children with ADHD had difficulties in movement and touch processing compared to healthy controls [13]. Furthermore, compared to healthy controls, children with ADHD and sensory processing difficulties showed increased behavioural and social problems [13]. Among children with ADHD, sensory processing disorders have been found related to sleep disturbance [14]. A study of 76 children aged 8 to 11 years showed that children with ADHD and atypical sensory profiles had a higher rate of sleep disturbance as compared to both children with ADHD and typical sensory profiles, and controls [14].

Weighted blankets are assumed to change physiological arousal by deep pressure stimulation from the weight of the blanket as well as from the movement of the filling in the weighted blankets [15]. Weighted blankets are available with different materials i.e., balls-, chains-, fibre- or granules filling. The use of a weighted blanket has been proposed to be an effective method for the treatment of sleep disturbances among children with ADHD, though the empirical evidence supporting this claim is sparce [16–19]. Only one crossover randomised controlled trial (RCT) (n = 94) has investigated the effect of weighted fibre blankets used for four weeks compared to a lighter control blanket among children with ADHD. This RCT showed an effect of the weighted blanket on total sleep time, sleep maintenance and decreased sleep disruption but found no effect on sleep onset latency [19].

In Denmark, it is not standard practice for child and youth psychiatric departments to provide weighted blankets to children with ADHD and sleep disturbances [20]. However, some departments allow these children to try weighted blankets as a potential aid. If the blankets prove effective, families can apply to their municipality for financial assistance to purchase one.

Study objectives

The primary objective of the trial is to compare the effect of a weighted blanket, relative to a non-weighted blanket, both blankets used every night and during daytime, on changes in actigraphy measured total night sleep time (TST) from one week before the intervention starts and again at end of treatment (4 weeks from baseline).

The secondary objectives are to compare the effect after 4 weeks on changes in (i) functioning impairment, (ii) sleep onset latency, (iii) number of awakenings during the study period, (iv) sleep efficiency, (v) ADHD core symptoms, (vi) child quality of life measures and (vii) parental stress. As an explorative objective we will investigate changes in sensory modulation.

To assess safety of the intervention, the occurrence of adverse and serious adverse events will be compared between the two interventions. If weighted blankets are effective on total sleep time, cost-effectiveness analysis will be conducted. Finally, we will investigate long-term effects, after two and five years of the interventions.

Methods and analysis

Trial design and setting

The SPIRIT (Standard Protocol Items for Randomized Trials) was followed in the writing of this protocol paper [21]. The study is structured as a superiority trial, applying a pragmatic parallel group, randomised controlled trial design. Patients will be randomly assigned 1:1 into two groups using computer-generated random numbers. Following randomisation, each patient will remain in their assigned treatment arm for the duration of the study. The allocation sequence will be stratified by age (5 to 8 years vs. 9 to 12 years), ADHD medication (yes vs. no) and use of melatonin/sleep medication (yes vs. no). The randomisation procedure will be implemented in REDCap [22] by an independent researcher not involved in data collection nor data management/ analysis. Participants and parents will not be fully blinded. However, by introducing a sham blanket, we will ensure an alignment of contextual factors (i.e., instructions concerning the use of the blanket and the experience of getting a blanket) in the two groups. Those who enrol the patients are blinded to group allocation while the clinician providing the intervention will be unblinded to allocation. Researchers will be blinded during all data assessment, management, and analysis. The trial is thus only semi-blinded. For a flow chart of the trial design and study procedure, see Figs. 1 and 2. The trial is hosted by the Parker Institute, a part of Copenhagen University Hospital Bispebjerg-Frederiksberg and performed in collaboration with the Child and Adolescent Mental Health Centre, Mental Health Services in the Capital Region of Denmark.

Fig. 1.

Flowchart

Fig. 2.

Study procedures

Patient and public involvement

The design of the study and the preparation of the protocol have been coproduced with healthcare professionals within the child mental health service as well as two patient research partners (PRP’s), both parents to affected children. One PRP had a daughter diagnosed with ADHD and the other PRP had a son diagnosed with both ADHD and autism spectrum disorder. The PRP’s were identified during routine care, and both had experiences with using weighted blankets. They both acknowledged the idea and purpose of the study, and participated in discussions of design, relevance, and feasibility of the trial. The family burden of participating in the study was evaluated prior to study start where PRP’s filled in the trial questionnaires in REDCap [22]. PRPs read and commented on the written participant information. We expect to involve patient organizations when disseminating the results.

Sample size and power considerations

We have not been able to detect any literature that defined what is the relevant minimal clinical important difference for TST among children with ADHD or other indirect populations. Our decision was based on other research that have investigated sleep patterns among children with ADHD and consensus among Danish experts [16, 19, 23]. A total of 340 patients are required, corresponding to approximately 170 individuals in each group. Assuming that the standard deviation of total sleep time is 46 min the study should have sufficient power (85%) to detect a between group target difference of 15 min, which we judge is a minimal clinically relevant difference to choose one treatment over another [16].

Trial population and eligibility criteria

The trial will include and randomise a minimum of 340 children (patients). Patients with an ADHD/ADD diagnosis and their caregivers will be recruited from the Child and Adolescent Mental Health Centre, Mental Health Services in the Capital Region of Denmark. The plan is to recruit 4 patients per week during the trial period. To ensure ongoing recruitment, we will use ongoing reminders to the clinical personal. If recruitment fails, trial manager will seek to recruit patients by screening the clinic’s daily timetable in the medical record for potential participants based solely on their age and diagnosis. If it is not feasible to recruit from the Child and Adolescent Mental Health Centre, and the Mental Health Services in the Capital Region of Denmark only, participants from private hospitals will be recruited. The last patients will be referred by March 2026 and have last visit in April 2026. All caregivers to patients aged 5 to 12 years who prior to enrolment had tried sleep hygiene advice and are found eligible for referral to testing of weighted blankets will be introduced to the project. Individuals will be eligible for study participation if they meet the following criteria:

1. Signed informed consent by the caregivers on behalf of themselves and their children.

2. Age 5 to 12 years (both included) at randomization.

3. Diagnosis of ADHD/ADD according to ICD-10 code F90.0, F90.1, F90.9 or F98.8.

4. Parent-reported and/or diagnosed sleep disturbances.

5. Patients must have tried usual care sleep hygiene advice, regardless of effect, managed by clinicians within 6 months prior to enrolment.

6. If treated with ADHD medication or/and melatonin/sleep medication the dose must be stable, at least two weeks prior to enrolment.

7. The child and caregiver have adequate mastery of the Danish language.

Individuals will be excluded from study participation if they have used any type of medical device class 1 weighted blanket before, are diagnosed with any diseases that markedly compromise the patient’s ability to adhere to the intervention (like severe or deep mental retardation, severe underweight, chronic respiratory or circulatory conditions, surgical implants, osteoporosis) or if another member of the household currently is, or previously has been enrolled in the trial.

Caregivers of potential patients will receive written information about the trial from their clinician (Supplemental material 4). Caregivers will be given oral and written information and asked for permission to be contacted. If the patient and their caregiver agree, trial personal will contact them by phone to screen for eligibility. Written information will also be sent by email. Caregivers will be informed that the sham blanket is not a weighted blanket, but both interventions will be presented with the same positive suggestion as potentially equally effective. Thus, caregivers will not be informed of the fact that one of the blankets is hypothesized to not have an effect. It is emphasized that participation is voluntary, and that consent can be withdrawn at any time. A minimum of 24 h is given for reflection on participation, before signing consent (Supplemental material 1, 2 and 3). The participating children are insured by the Danish Patient Insurance Association.

Management as usual (applying for both groups)

Patients in both groups will continue usual treatment as part of standard care for children with ADHD, which consists of sleep hygiene [24], they may also receive psychoeducation, cognitive behavioural theory and medications such as melatonin or ADHD medication.

Experimental intervention group

The intervention group will receive usual treatment and a weighted blanket classified as a medical device class 1 as an add on to usual treatment. To the best of our knowledge no research has been conducted comparing various types of weighted blankets with regards to effects in this population or in other populations. According to the clinicians’ experiences, the specific type of weighted blanket is less significant, as the deep pressure stimulation created by the movement of the filling is thought to be the key factor in providing the therapeutic effect. We provide a choice between eight different blankets with different fillings and different weight classes (4 to 12 kg [kg]). The blanket types include: one 5 kg blanket with a granulate filling and few small air-filled plastic beads; one 6 kg blanket with a combination of granulate and large plastic balls; two blankets with large unorganized balls weighing respectively 7 kg and 10 kg; three blankets with organised large balls weighing respectively 4, 7 and 10 kg or one blanket with chains weighing 12 kg. The choice of weighted blanket is to the extent possible taken by the patient after having tried all blankets. If the patient is not able to choose a blanket, the clinician will help.

Patients and caregivers in the intervention group will be guided by a clinician in using the weighted blanket for four weeks (28 days and nights). It should be used every night and at least one time during daytime to induce a daily break for a minimum of 5–10 min. The use of the weighted blanket during daytime is based on clinical experience, where incorporating a weighted blanket into the child’s daily routine fosters relaxation and reduces the feeling of being over- or under stimulated, which may improve sleep quality. The patient should use the blanket by either lying under it, on it or against it. All guidance is in line with usual practice in the Child and Adolescent Mental Health Centre. The clinician will also provide information to patients and parents about the concept of sensory integration and the possible effect of weighted blankets. After end of treatment, all participants will return the weighted blanket.

Control comparator group

Patients in the control group will receive usual treatment and a sham intervention in the form of a non-weighted blanket. Patients will be asked to choose one out of two different sham blankets. The blankets will be the same size as the weighted blanket but filled with fibre and have a weight of 900 g–1.300 g. Patients in the control group will also be guided by a clinician in using the control blanket every night and at least one time during daytime for four weeks. As in the intervention group, the clinician will also provide information about the concept of sensory integration. After end of treatment, all participants will return the non-weighted blanket.

Concomitant therapy

Concomitant treatment with any weighted blankets is not permitted. All other types of treatments are allowed, but patients will be encouraged not to change or initiate any other treatments during the study period. Other concomitant therapies based on either self-report from the caregivers or from patient records will be recorded during the study period for all patients.

Treatment adherence

Treatment adherence among patients will be assessed by a daily mobile phone text message with a yes/no option for using the blanket as prescribed completed by the caregiver. Adherence to the weighted blanket intervention is defined as reported use (day and night) 60% of the intervention period.

Outcome measures

Table 1 lists the outcome measures and the time points at which they are collected.

Table 1.

Summary of measures to be collected and timeframes

Variable	Baseline	End of treatment	Two years follow-up	Five years follow-up
Primary outcome Total sleep time (TST)	x	x
Key secondary outcomes
Functional level (WFIRS-P)	x	x	x
Sleep onset latency (SOL)	x	x
Other secondary outcomes
Sleep efficiency (SE)	x	x
Wake after sleep onset (WASO)	x	x
ADHD-core symptoms (ADHD-RS-IV)	x	x	x
Parental stress scale (PSS)	x	x
QoL (WHO-5 Child Wellbeing Index)	x	x	x
Exploratory outcomes
Sensory processing (SPM-2)	x	x	x
Economical evaluation (Work Productivity and Activity Impairment Questionnaire (WPAI-GH; Work Productivity and Activity Impairment Questionnaire (WPAI-GH))	x	x	x
Safety
Adverse events		x
Serious adverse events		x
Long-term follow-up (register based)
School Grades			x	x
Referal to health specialists			x	x
Upper secondary education			x	x

Primary outcome

Primary outcome is change in TST per day from baseline to end of treatment. TST is defined as the time of total sleep episode minus the awake time (the entire time spent sleeping) and reported in minutes per day [25]. TST per day will be measured using actigraphy in form of MotionWare 8 (The MotionWare 8^®—CamNtech MotionWare). The sleep analysis will be based on algorithms from the program. The epoch length on measurement is set to 30 s.

The MotionWare 8 has been validated among children (mean age 5.4 years; SD 1.57) with autism spectrum disorders [26]. Measurements from at least 5 nights have been recommended to obtain reliable actigraph measures of sleep for children and adolescents [27]. Patients will wear the actigraphy on their non-dominant wrist at baseline 7–10 days before randomization (week 0) and the last 14 consecutive days of the trial (week 3 and 4). The patients can choose if they want to use the actigraphy during daytime while use during night is mandatory. To ensure that the actigraphy is used at follow up, a structured telephone call is scheduled around day 14 after randomisation where the caregivers will be reminded of when to start using the actigraphy again.

Secondary outcomes

Key secondary outcomes include changes in functional impairment and changes in sleep onset latency (SOL) from baseline to end of treatment. Functional impairment is measured using the caregiver rated Weiss Functional Impairment Rating Scale (WFIRS-P) [28]. The WFIRS-P is a 50-item scale assessment tool that can be used to assess functional impairment in 5 to 19-year-old children. It contains six domains: (A) Family; (B) School and learning; (C) Life skills; (D) Child’s self-concept; (E) Social activities; and (F) Risky activities. Each item is rated on a four-point scale from 0 (‘never or not at all’) to 3 (‘very often or very much’) or rated as ‘not applicable’. The instrument uses a Likert scale with a rating of 2 or 3 being seen as clinically impaired function. The mean of all scored items for each domain will be calculated. Furthermore, a single overall WFIRS-P score will also be calculated as the average of the six domain scores [28]. SOL refers to the period between turning lights out to go to sleep and falling asleep. SOL will be measured using actigraphy and will be reported as minutes per day.

Other secondary outcomes, to be detailed in subsequent publications, will encompass changes in sleep efficiency (SE) and wake after sleep onset (WASO) assessed via actigraphy from baseline to the end of treatment. SE is the actual sleep time expressed as a percentage of the total time in bed (the time elapsed between “lights out” and “get up time). WASO is defined as number of minutes scored as wake during sleep period [25]. Caregiver rated secondary outcomes include changes from baseline to end of treatment in ADHD core symptoms, parental stress and child quality of life. ADHD core symptoms are measured with the Attention Deficit Hyperactivity Disorder Rating Scale (ADHD-RS-IV) parent version [29]. The ADHD-RS instrument determines the frequency and severity of ADHD symptoms and impairments among children aged 5 to 17 years during the last six month. It contains 26-item questionnaire including the 18 original ADHD-RS-IV items supplied with 8 conduct problem items. All items are rated on a 4-point Likert scale (0 to 3), where 0 represents never or rarely, 1 is sometimes, 2 is often, and 3 is very often. From the item scores, a total score ranging 0–78 will be calculated. Further, three sub-scores will be calculated; inattentive scale: range 0–27, hyperactive/impulsive scale: range 0–27, and conduct scale: range 0–24 [30]. Parental stress life is measured by the Parental Stress Scale (PSS) [31]. The PSS is an 18-item questionnaire assessing parents’ feelings about their parenting role, exploring both positive aspects (e.g., emotional benefits, personal development) and negative aspects of parenthood (e.g., demands on resources, feelings of stress). Responses are scored as follows: strongly disagree, disagree, undecided, agree, strongly agree. The item scores are then summed. Parental stress scores range from 18 to 90, with lower scores indicating lower levels of parental stress. Changes in child quality of life score will be measured using The World Health Organisation - Child Well-Being Index (WHO-5) [32] modified version. The WHO-5 Child Wellbeing Index is a simple self-reported measure of children’s psychological wellbeing. It consists of five, positively phrased questions for use with children aged nine and above. A wellbeing score is calculated by summing values of the items and multiplying the sum by 5 to obtain a final score ranging from 0 to 100. The higher the score, the higher a child’s wellbeing. The modified version is slightly simplified with five answering options instead of six and has been found suitable for use with children aged 5 to 17 [33].

Exploratory outcomes

Exploratory outcomes include changes from baseline to end of treatment in Sensory Processing Measure 2 (SPM-2) [34]. The SPM-2 Home form (caregiver form) is normed for children aged 5 to 12 years and provides a complete picture of children’s sensory processing difficulties at home during the last month. The SPM-2 home form consists of 80 Likert-type items and includes eight different scales: social participation, vision, hearing, touch, taste and smell, body awareness, balance and motion and finally planning and ideas, which capture related but separate aspects of sensory processing difficulties. Responses never, occasionally, frequently, or always correspond to the numeric values one to four respectively, to indicate the frequency of behaviours.

A total sensory systems raw score will be calculated with a higher score suggesting more severe dysfunction. Raw scores will be also converted to T-scores and percentile scores that can fall into three ranges: Typical functioning (T-score range 40 to 59) which indicates that the child’s behavioral and sensory functioning is similar to that of typical child; T-score range 60 to 69 which indicates moderate difficulties in functioning, or Tscores ≥ 70 which indicate severe difficulties in functioning [35].

Health economics

Health economic evaluation will be performed if weighted blankets shows superiority over the control compare group (non-weighted blanket) using quality-adjusted life years (QALY’s) for children and caregivers based on the EuroQol 5-Dimension Youth (EQ-5D-3 L-Y) [36] and caregivers with EuroQoL 5-Dimension 3-Level (EQ-5D-3 L) [37, 38]. We will assess productivity loss among caregivers using the work productivity and activity impairment questionnaire - general health (WPAI-GH) [39]. We will investigate within-trial cost-effectiveness of the intervention by assessing HRQoL and incremental cost per QALY. To explore caregiver productivity, loss specifically related to their child’s health, we will further add three questions corresponding to questions 2, 5 and 6 but where the wording “your health problems” will be replaced with “your child’s health problems”. Question 2 will then be reworded from: “During the past seven days, how many hours did you miss from work because of your health problems?” to: “During the past seven days, how many hours did you miss from work because of your child’s health problems?

Long-term follow-up

Two years after end of trial, patients accepting a follow-up questionnaire will be contacted by digital post and asked to answer the end of trial questionnaire again including a question about usage of weighted blankets during the last two years. The patients will also be followed in the Danish registers: Danish National Test Program, the Student Register with information on grades, and the Danish Health Insurance Register with information on referral to health specialists two and five years after end of trial. For patients aged ≥ 10 years at the end of trial, information on upper secondary education will be available on Statistics Denmark. Changes from end of treatment to two to five years stratified by type of blanket will be explored on secondary outcome questionnaire measures and register based information.

Adverse and serious adverse events

The number of patients with adverse events (AE) or serious adverse events (SAE) during the intervention period will be assessed. No formal data monitoring committee will be composed. The investigator and clinical staff will monitor each patient for evidence of adverse events (AEs) at the second meeting after the patient has used the motion watch and at the two trial phone calls at mid-study and at end of trial. Trial manager is further automatically noticed from the electronic journal system whenever a patient (in the active trial, or as part of the follow-up study) has a serious adverse event. The investigator will assess and record any AE/SAE in detail including the date of onset, description, severity, duration and outcome, relationship of the AE/SAE to study treatment, and any action(s) taken. The investigator will record if the AE/SAE is probably related, probably not related or not related to the trial intervention.

Patient discontinuation

A patient or caregiver who no longer wishes to participate in the trial can withdraw his/her informed consent at any time without explanation, and without consequences for the patient’s further treatment. The investigator or study sponsor may choose to discontinue the patient’s participation for any reason, including an AE/SAE, safety concerns or failure to comply with the protocol. We will seek to obtain follow-up questionaries also from patients who wish to discontinue.

Data mangement

All data will be stored in REDCap, which meets all regulatory standards and allow management of all activities related to clinical trials. The database is branched to ensure accurate data collection.

Statistical analyses

Continuous endpoints will be analysed using an analysis of covariance (ANCOVA) model with randomised treatment, stratification groups as factors and the baseline endpoint value as covariate. The analysis will incorporate randomised treatment, and stratification groups as covariates. All results from statistical analyses on the primary and key secondary endpoints will be presented alongside two-sided 95% confidence intervals (CIs) and corresponding p-values (with superiority defined as p < 0.05). Exploratory analyses of secondary endpoints will not be adjusted for multiple comparisons, and caution should be exercised in drawing definitive conclusions regarding treatment effects from these. A 95% confidence interval excluding differences lower than 15 min in TST between groups will be interpreted as indicating the absence of a clinically meaningful difference [40]. The main analyses will adhere to the Intention-to-Treat (ITT) principle. This approach evaluates the effect of the planned treatment regimen rather than the actual treatment received, irrespective of adherence. Hence, patients will be analysed based on their allocated treatment groups regardless of treatment adherence, withdrawals, or crossover phenomena. Missing data will be imputed from eligible patients within the same randomised treatment group, and the outcomes will be pooled using Rubin’s rules [41].

Contextual factors of importance

Interactions between intervention status and baseline patient groupings on sex, age, sensory profiling and medication status will be prioritised as priori subgroups analyses for the primary and key secondary outcomes [42]. Sex and age will be analysed as a categorical variable (girl or boy; 5 to 8 y and 9 to 12 y) to avoid assumptions of linearity (or the complexity of fitting polynomial terms) and for ease of presentation. Sensory profiling will be dichotomised as normal vs. abnormal. Medication status will be dichotomised as yes vs. no. These pre-planned analyses will be conducted by the inclusion of appropriate interaction terms in the statistical models. This will mitigate the problems of multiple testing due to many subgroup comparisons. We recognize that statistical power in subgroups will vary with sample size and provide plots of detectable effect size versus sample size for reference [42]. Prior to end of trial, a detailed statistical analysis plan will be published. Statistical analyses will be performed in SAS studio.

Trial status

The first participant was recruited on December 19, 2023, and the trial is currently recruiting. When this manuscript was submitted for publication (March 13, 2025), a total of 82 patients had been included in the trial. We expect recruitment to be completed 1st April 2026.

Discussion

This study describes the methodology of the Sweet Dreams RCT, comparing weighted blankets with non-weighted sham blankets on sleep disorders and dysfunction in children with ADHD aged 5–12 years. This trial is expected to contribute with further knowledge on the potential benefits and harms of weighted blankets and provide evidence that can reduce sleep disturbances among children with ADHD. Knowledge from this trial may also enable a more standardized approach to these patients, potentially reducing inequality in treatment opportunities.

There are several strengths to this pragmatic trial. This trial will be one of twoRCT’s investigating the effects of weighted blankets in children with ADHD. A strength of this trial is the use of a sham control group, enabling a standardization of contextual factors in both groups. Moreover, it is the largest trial conducted with a pre-specified enrollment of 340 participants. Another strength is the use of an objective measure of sleep, preventing a biased measurement of the outcome. Furthermore, the randomization is performed by a researcher not related to the project and outcome assessors and researchers will be blinded through data collection, management and analysis. Finally, the evaluation of cost-effectiveness of weighted blankets is relevant when implementing the intervention in healthcare settings.

A weakness is, that the clinicians providing the intervention are not blinded to the allocation, which could potentially lead to bias, although the researchers analyzing the data are. Furthermore, the pragmatic nature of this trial, while being highly transferable to clinical practice, may provide more information on the effectiveness than on the efficacy of the intervention.

The results from this RCT will, thus, provide new evidence of the effectiveness of the use of weighted blankets to address sleep problems and possible functional impairment among children with ADHD. The research findings could establish an evidence-based, non-pharmacological approach for children with ADHD and sleep problems allowing for a non-pharmacological alternative in a field where interventions are limited.

Results will be disseminated in academic peer-reviewed journals and in platforms/formats that are accessible to the public. Furthermore, the results will be presented to relevant patient organisation.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Abbreviations

ADHD

Attention deficit hyperactivity disorders

CI

Confidence interval

RCT

Randomised controlled trial

PRP

Patient research partners

TST

Total night sleep time

Kg

Kilograms

WFIRS-P

Weiss Functional Impairment Rating Scale

SOL

Sleep onset latency

SE

Sleep efficiency

WASO

Wake after sleep onset

ADHD-RS-IV

ADHD-core symptoms

PSS

Parental stress scale

WHO-5

The World Health Organisation - Child Well-Being Index

SPM-2

Sensory processing measure 2

WPAI-GH

Work productivity and activity impairment questionnaire

EQ-5D-3 L

EuroQoL 5-Dimension 3-Level

QALY

Quality-adjusted life years

EQ-5D-3 L-Y

EuroQol 5-Dimension Youth

AE

Adverse event

SAE

Serious adverse event

Author contributions

Ina Olmer Specht (IOS) is the guarantor and is together with JFR responsible for the conception and design. IOS and JFR are the primary investigators; they conceived the study and led the proposal and protocol development. All authors contributed to the study design and protocol development. IOS, JFR, RC, SCL, EG-N participated in the sample size and power calculation and in describing the statistical procedure. EG-N and RC developed the allocation and randomisation procedures. EG-N and CT act as clinical investigators providing the interventions. JFR, IOS and EG-N drafted the manuscript. All authors edited, read and approved the final manuscript.

Funding

Open access funding provided by Copenhagen University

This protocol and the study are funded by the Independent Research Fund Denmark (grant no.: 2096-00071B) received by Ina Omer Specht, Aase og Ejnar Danielsens Fond (grant no.: 23-10-0294) and Dagmar Marshalls fond also received by Ina Omer Specht, and Lundbeckpuljen til sundhedsfaglig forskning og Rigshospitalet/UCSF (grant no.: F-23859-01) received by Elisabeth Ginnerup-Nielsen. The Parker Institute is funded by a core grant from the OAK Foundation (OCAY-13-309). Funding is an ongoing process. All current and future sources of support (including technical and financial support) provided for this study are disclosed in the written information material and in publication of the study results. The funders and sponsor will have no role in the design and conduct of this study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

Data availability

No datasets were generated or analysed during the current study.

Declarations

Ethics approval and consent to participate

One caregiver will respond to trial questionnaires and sign informed consent on behalf of themselves and their child before commencing any study related procedures. The other caregiver not responding to trial questionnaires will only consent on behalf of their child (Supplemental material 1, 2 and 3). The study personnel will seek to inform each child about study procedures based on their age and cognitive level.

The study is approved by the Medical Research Ethics Committees and The Danish National Committee on Health Research Ethics (jr.no.: 2401653 and 21028268, respectively), and registered in ClinicalTrials.gov NCT06194162.

In accordance with the principles of the Helsinki declaration, all results of the study, positive as well as negative and inconclusive will be published.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.