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Assessing the Effect of Cool Roofs on Health Using Smartwatches in Niue

A Randomized Controlled Trial (RCT) Evaluating the Effects of Cool Roofs on Health Outcomes Using Smartwatches in Niue

Status
Completed
Phases
Unknown
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT06571019
Acronym
REFLECT
Enrollment
187
Registered
2024-08-26
Start date
2024-09-04
Completion date
2026-01-31
Last updated
2026-02-27

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Active Minutes, All-day Steps, Awake Duration, Distance Walked, Heart Rate, Moderate-intensity Activity Minutes, Sleep Quantity, Sleep Score, Time in Sleep Stages, Vigorous-intensity Activity Duration

Keywords

Hot Temperature, Humidity, Housing, Wearable, Smartwatch, Heart rate, Cardiovascular, Physical activity, Sleep, Cool roof, Heat stress

Brief summary

Ambient air temperatures in the Pacific have broken record highs in 2024. Solutions are needed to build heat resilience in communities and adapt to increasing heat from climate change. Sunlight-reflecting cool roof coatings may passively reduce indoor temperatures and energy use to protect home occupants from extreme heat. Occupants living in poor housing conditions in the Pacific are susceptible to increased heat exposure. Heat exposure can instigate and worsen numerous physical, mental and social health conditions. The worst adverse health effects are experienced in communities that are least able to adapt to heat exposure. By reducing indoor temperatures, cool roof use may promote heart health, sleep and physical activity in household occupants. The long-term research goal of the investigators is to identify viable passive housing adaptation technologies with proven health benefits to reduce the burden of heat stress in communities affected by heat in Niue. To meet this goal, the investigators will conduct a randomized controlled trial to establish the effects of cool roof use on heart rate, sleep and physical activity in Niue.

Detailed description

Increasing heat exposure from climate change is causing and exacerbating heat-related illnesses in millions worldwide - particularly in low-resource settings. June 2024 was the 13th consecutive hottest month on record globally - shattering previous records. Heat exposure can instigate and worsen health conditions, including cardiovascular, metabolic, endocrine and respiratory disease, heat-related illnesses, pregnancy complications, and mental health conditions. Adaptation is essential for protecting people from increasing heat exposure. The built environment, especially homes, is ideal for deploying interventions to reduce heat exposure and accelerate adaptation efforts. However, there currently is a lack of evidence on a global scale - generated through empirical studies - guiding the uptake of interventions to reduce heat stress in low-resource settings. Pacific Islands and other small island developing states are among the most vulnerable to the adverse impacts of climate change and are likely to experience increases in ambient air temperature over the coming decades. People in Niue are exposed to heat and humidity year-round. The Pacific Islands have a large burden of non-communicable diseases (NCDs), with nearly three-quarters of deaths due to NCDs. The combined burden of heat and NCDs places Pacific Island populations at greater risk of adverse health effects from heat extremes. Sunlight-reflecting cool roof coatings passively reduce indoor temperatures and lower energy use, offering protection to home occupants from extreme heat. The investigators therefore aim to conduct a randomized controlled trial investigating the effects of cool roofs on heart rate, sleep and physical activity using smartwatches in Niue. The trial will quantify whether cool roofs are an effective passive home cooling intervention with beneficial health effects for vulnerable populations in Niue. Findings will inform regional and global policy responses on scaling cool roof implementation to protect people from increasing heat exposure driven by climate change.

Interventions

Cool roofs are a heat-reflecting material that can be applied to existing household roofing in the form of a liquid-applied membrane. Cool roofs work by increasing solar reflectance (the ability to reflect the visible wavelengths of sunlight, reducing heat transfer to the surface) and thermal emittance (the ability to radiate absorbed solar energy) thereby reducing the amount of heat transferred into the home.

Sponsors

Aditi Bunker
Lead SponsorOTHER
Heidelberg University
CollaboratorOTHER
London School of Hygiene and Tropical Medicine
CollaboratorOTHER
Rutgers University
CollaboratorOTHER
Secretaría de Educación Pública, México
CollaboratorOTHER_GOV
University of Ouagadougou, Burkina Faso
CollaboratorOTHER
Indian Institute of Public Health, India
CollaboratorOTHER
Labfront
CollaboratorINDUSTRY
Cognifit
CollaboratorUNKNOWN
Resene
CollaboratorINDUSTRY
Habitat for Humanity
CollaboratorOTHER
The Tindall Foundation
CollaboratorOTHER
Pacific Community
CollaboratorOTHER
Wellcome Trust
CollaboratorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
DOUBLE (Investigator, Outcomes Assessor)

Masking description

Trial participants will be aware of the intervention to which they have been allocated, and the research fieldworkers will be aware of the intervention allocation. The trial steering committee members and trial statistician will remain blinded until the end of trial period and data collection.

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes

Inclusion criteria

Participant criteria: * Consenting adult aged 18 years and over. * Expected to be available to participate in the study for at least nine months in the next 12 months. * Willing and able to wear a smartwatch. Household criteria: * House has a metal roof. * House is single-story.

Exclusion criteria

Participant criteria: * One participant per household * Does not have a smartphone with an internet connection that can connect to the smartwatch. Household criteria: * Unstable house structure that does not permit the application of cool roof materials. * Inaccessible by the research team. * Significant roof damage defined as any penetrative roof defect that results in a hole in the roof OR over 25% of the roof rusted.

Design outcomes

Primary

MeasureTime frameDescription
Heart rateSmartwatches will be worn for two consecutive weeks per month. Eight measurement points will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.Heart rate in beats per minute measured at 15-second intervals using Garmin Vivosmart 5 devices.

Secondary

MeasureTime frameDescription
All-day stepsSmartwatches will be worn for two consecutive weeks per month. Eight measurement points will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.The number of steps measured daily using Garmin Vivosmart 5 devices.
Active minutesSmartwatches will be worn for two consecutive weeks per month. Eight measurement points will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.The total number of minutes of active exercise daily using Garmin Vivosmart 5 devices.
Distance walkedSmartwatches will be worn for two consecutive weeks per month. Eight measurement points will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.The total distance walked daily using Garmin Vivosmart 5 devices.
Moderate-intensity activity minutesMeasuSmartwatches will be worn for two consecutive weeks per month. Eight measurement points will be taken: one at barements will be taken continuously for 12 months. Participants will be asked to wear their smartwatch for at least two weeks every month.The total number of minutes of moderate-intensity activity daily using Garmin Vivosmart 5 devices.
Vigorous-intensity activity durationSmartwatches will be worn for two consecutive weeks per month. Eight measurement points will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.The total number of minutes of vigorous-intensity activity daily using Garmin Vivosmart 5 devices.
Sleep quantitySmartwatches will be worn for two consecutive weeks per month. Eight measurement points will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.The number of hours spent asleep each night using Garmin Vivosmart 5 devices.
Time in sleep stagesSmartwatches will be worn for two consecutive weeks per month. Eight measurement points will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.The number of hours spent in sleep stages each night using Garmin Vivosmart 5 devices.
Awake durationSmartwatches will be worn for two consecutive weeks per month. Eight measurement points will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.The number of hours spent awake during sleep time each night using Garmin Vivosmart 5 devices.
Sleep scoreSmartwatches will be worn for two consecutive weeks per month. Eight measurement points will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.The Garmin sleep score (0-100) each night using Garmin Vivosmart 5 devices.

Countries

Niue

Contacts

PRINCIPAL_INVESTIGATORCollin Tukuitonga, Sir. Dr.

University of Auckland, New Zealand

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 28, 2026