Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12625000795493
Ethics application status
Approved
Date submitted
1/07/2025
Date registered
25/07/2025
Date last updated
25/07/2025
Date data sharing statement initially provided
25/07/2025
Type of registration
Prospectively registered

Titles & IDs
Public title
Heat Outcome Trial (HOT) Text – Pilot Randomised Controlled Trial of a tailored text messaging intervention for heat adaptation in older Australians
Scientific title
Pilot randomised controlled trial of a tailored text messaging intervention for heat adaptation in older Australians: Heat Outcome Trial (HOT) Text
Secondary ID [1] 314613 0
Nil known
Universal Trial Number (UTN)
U1111-1324-0090
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
cardiovascular disease 337747 0
respiratory disease 337749 0
renal disease 337751 0
metabolic disease 337912 0
neurological disease 337915 0
mental health condition 337917 0
Condition category
Condition code
Cardiovascular 334076 334076 0 0
Coronary heart disease
Respiratory 334079 334079 0 0
Asthma
Respiratory 334080 334080 0 0
Chronic obstructive pulmonary disease
Renal and Urogenital 334082 334082 0 0
Kidney disease
Metabolic and Endocrine 334239 334239 0 0
Diabetes
Neurological 334244 334244 0 0
Other neurological disorders
Public Health 334265 334265 0 0
Health promotion/education
Public Health 334266 334266 0 0
Health service research

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Brief Title: HOT Text
Currently, generic heat warnings are the standard of care in public health notifications. However, such communication may lack efficiency, fail to reach the target population, or may lead to suboptimal behaviour change if it isn't timely, accessible, consistent or considered trustworthy. Understanding the barriers to receiving heat warning information will assist in mitigating health impacts from extreme heat exposure. We therefore propose to evaluate whether a tailored text messaging intervention can reduce patient reported heat symptoms, increase adoption of heat adaptive behaviours and reduce utilisation of health services during and after extreme heat days for older Australians (65 years and older).

Materials provided: No physical materials provided.

Procedures: This will be conducted as a pilot study. Trial participants will be randomly assigned to one of two arms:
Control arm - this group will receive a heatwave warning forecast and general information on managing heat;
Intervention arm - this group will receive a heatwave warning forecast and a tailored, disease- and location-specific advice messages via text (Short Message Service -SMS). Message length is estimated to be approximately 150 words or less, and will be one-way interactions i.e., participants will not be required to or able to provide a response. The intervention will be triggered by a rule-based algorithm using both Bureau of Meteorology (BOM) heat alert data, and participant (demographic, vulnerabilities, health status) data. Messages will be selected and tailored according to a message library developed by the research team (and informed by expert clinicians). Messages will be text-based and contain a link for accessing additional information e.g., health management actions. An example of tailoring may be:
"Hi [Name], Pilot Heat Trial: Extreme heat in [LOCATION=district/post code] from [DATE] to [DATE]. You are at higher risk of heat distress. Stay cool, hydrated, and watch for signs of heat exhaustion. To find out more on this, Click Here. Below, we provide additional tips tailored to your condition [ACTION1: e.g. Speak to your GP about a COPD action plan] [ACTION 2: e.g. Monitor your symptoms for any signs of worsening respiratory conditions such as breathlessness, cough, and mucus production] [ACTION3: 3 e.g. Continue to monitor symptoms for several days after heatwave event]” where actionable content is specific to each participant.

Post-intervention surveys for outcomes and intervention acceptability will be conducted, followed by focus groups to better understand the user experience (feasibility, barriers, and facilitators).

Who: The research team, comprising investigators with expertise spanning information technology, climate and health, clinical care, consumer engagement, and research design, will deliver the intervention. Clinicians will inform the tailored text message content.

Mode of delivery: MS Teams teleconferencing platform will be used for the Focus Group interviews. Survey data will be collected via the REDCap platform. Our experienced software development team will employ commercial off-the-shelf (COTS) technology platforms which will integrate participant data and weather data (from the Bureau of Meteorology) including heatwave warning data, to tailor messages. The virtual intervention will issue text messages facilitated though Amazon Web Services.

Frequency of intervention: text message intervention will be delivered two days prior to forecast heat event, followed by a text message one day prior to the event.

Intervention location: This pilot study will be conducted online at participants’ preferred location (e.g., place of residence) within the following three states: NSW, SA and VIC.

How well: Intervention fidelity will be assessed through message compliance and engagement metrics e.g., percentage of messages opened, via survey.
Intervention code [1] 331241 0
Prevention
Intervention code [2] 331242 0
Lifestyle
Comparator / control treatment
Participants will receive general information on managing heat prior to an extreme heat event via SMS. Message length is estimated to be approximately 100 words or less. Message content will contain weather data about an upcoming heatwave event and general health advice about staying cool during extreme temperatures.
Control group
Active

Outcomes
Primary outcome [1] 341742 0
Changes in heat-related symptoms
Timepoint [1] 341742 0
Baseline, 3 days post-completion of the warning period.
Secondary outcome [1] 448575 0
Health service attendance
Timepoint [1] 448575 0
Baseline, 3 days post-completion of the warning period
Secondary outcome [2] 449016 0
Intervention usability
Timepoint [2] 449016 0
7 days post-completion of the warning period
Secondary outcome [3] 449017 0
Exploring participant experience of intervention including feasibility, acceptability barriers and facilitators via a qualitative focus group interview using a semi-structured interview guide. Focus group interviews will be conducted via the MS Teams platform (Macquarie University Enterprise subscription account). Each focus group interview will take approximately one hour to complete. After storing data on the project's Macquarie University enterprise SharePoint, all data on the MS Teams cloud account will be deleted.
Timepoint [3] 449017 0
4 weeks post-completion of the warning period
Secondary outcome [4] 449072 0
Adverse effects of the co-design workshops, survey and focus groups through sharing of personal information and experiences. Adverse effects of trial may include confusion from receiving conflicting trial advice and conflicting heat messages from government agencies.
Timepoint [4] 449072 0
3 days post-completion of the warning period, 7 days post-completion of the warning period
Secondary outcome [5] 449081 0
User compliance
Timepoint [5] 449081 0
3 days post-completion of the warning period
Secondary outcome [6] 449083 0
User engagement metrics
Timepoint [6] 449083 0
3 days post-completion of the warning period
Secondary outcome [7] 449580 0
User engagement metrics
Timepoint [7] 449580 0
3 days post-completion of the warning period

Eligibility
Key inclusion criteria
Participants with chronic conditions will be recruited, including those with cardiovascular, respiratory or renal diseases, as well as individuals taking medications that increase the risk of heat-related illnesses (e.g., anticholinergics). Participants will meet the following eligibility criteria:
Adults aged 65 years and older residing in Australia
Any sex, ethnicity and medical background
Possess a mobile phone and an Australian number
Able to read and communicate in English
Willingness to provide informed consent and to participate and comply with study requirements
Minimum age
65 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Adults younger than 65 years or residing outside of Australia
Residing in nursing home or aged care facilities
Participation in another risk communication trial for heat adaptation at time of study

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)
Allocation concealed by central randomisation by computer
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation: Computer-based random number generation
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s

The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Pilot study - aim to recruit approximately 1000 participants for a pilot trial (Arms: 500 intervention, 500 - comparator/control) to assess feasibility of the study

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
1/10/2025
Actual
Date of last participant enrolment
Anticipated
30/12/2025
Actual
Date of last data collection
Anticipated
31/05/2026
Actual
Sample size
Target
1000
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
NSW,SA,VIC

Funding & Sponsors
Funding source category [1] 319173 0
University
Name [1] 319173 0
Macquarie University
Country [1] 319173 0
Australia
Primary sponsor type
University
Name
Macquarie University
Address
Country
Australia
Secondary sponsor category [1] 321638 0
None
Name [1] 321638 0
Address [1] 321638 0
Country [1] 321638 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 317757 0
Macquarie University Human Research Ethics Committee Medical Sciences
Ethics committee address [1] 317757 0
Ethics committee country [1] 317757 0
Australia
Date submitted for ethics approval [1] 317757 0
20/02/2025
Approval date [1] 317757 0
14/04/2025
Ethics approval number [1] 317757 0
18563

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

Contacts
Principal investigator
Name 142034 0
Prof Enrico Coiera
Address 142034 0
Level 6, 75 Talavera Rd, Macquarie University, 2109, NSW
Country 142034 0
Australia
Phone 142034 0
+61 2 9850 2403
Fax 142034 0
Email 142034 0
[email protected]
Contact person for public queries
Name 142035 0
Dr Hania Rahimi Ardabili
Address 142035 0
Level 6, 75 Talavera Rd, Macquarie University, 2109, NSW
Country 142035 0
Australia
Phone 142035 0
+61 2 9850 9419
Fax 142035 0
Email 142035 0
[email protected]
Contact person for scientific queries
Name 142036 0
Enrico Coiera
Address 142036 0
Level 6, 75 Talavera Rd, Macquarie University, 2109, NSW
Country 142036 0
Australia
Phone 142036 0
+61 2 9850 2403
Fax 142036 0
Email 142036 0
[email protected]

Data sharing statement
Will the study consider sharing individual participant data?
Yes
Will there be any conditions when requesting access to individual participant data?
Persons/groups eligible to request access:
• Researchers
Conditions for requesting access:
• Yes, conditions apply:
• Requires review on a case-by-case basis by the trial custodian, sponsor or data sharing committee
• Requires a scientifically sound proposal or protocol
• Requires approval by an ethics committee
• Requires a data sharing agreement between data requester and trial custodian or sponsor
What individual participant data might be shared?
• De-identified individual participant data:
• All outcomes data
• Published results
• Primary outcome(s)
What types of analyses could be done with individual participant data?
• Systematic reviews and meta-analyses
• Studies exploring new research questions
When can requests for individual participant data be made (start and end dates)?
From:
After publication of main results
To:
A finite period of: 15 years
Where can requests to access individual participant data be made, or data be obtained directly?
• Email of trial custodian, sponsor or committee: [email protected]

Are there extra considerations when requesting access to individual participant data?
No


What supporting documents are/will be available?

TypeCitationLinkEmailOther DetailsAttachment
Ethical approval    Approval Letter_15_04_2025.pdf


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.