Perceptions of Weather Risks and Climate Beliefs Among the Hong Kong General Public

Study Overview
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Brief Summary
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Background: Local abnormal heat events may be used as proxies for communicating the health impacts of climate change when people physically feel the effects to reduce the psychological distance of climate change and improve public engagement with climate and weather risk. However, there are concerns that this strategy may be more effective for climate believers, and that it may somewhat compromise the scientific precision because it may lead to erroneous beliefs that climate change is merely characterized by temperature rises or extreme heat but ignore other extreme weather events such as flood and extreme cold, and that cold spells are interpreted as evidence of no climate change. None of these potential effects and concerns has been tested. Aims: This proposed study is aimed to explore patterns of climate beliefs and their influences on perceptions of heat-related risks and responses to heat health warnings in the general public of Hong Kong; (2) Test the preliminary effects of a revised heat health warning (RHHW) that incorporates information about the health impacts of climate change into existing heat health warning on perceived heat-related risk and climate beliefs. Design and subjects: This will be a mix-methods study comprising in-depth qualitative interviews, a population-based cohort survey and a pilot randomized control trial (RCT). Subjects will be the general Hong Kong Chinese adults aged ≥18 years. Main outcome measures: Latent class analysis will be conducted to examine patterns of climate beliefs while structural equation modelling to test the relationships among climate beliefs, perceived heat-related risks and behavioural responses to heat warnings. Qualitative data will be analysed using thematic content analysis while the effect of RHHW will be tested using t-test and linear regression models.

Official Title
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Climate Change Beliefs, Perceived Risk of Heat Stress and Responses to Heat Health Warnings Among the General Public of Hong Kong: a Mixed-methods Study

Conditions
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Weather Risk Perception

Intervention / Treatment
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* Behavioral: Heat risk and pro-environment behavior message


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Participants should own a mobile phone and be able to read Chinese. Exclusion Criteria: Participants with no mobile phone or cannot understand Chinese will be excluded.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Health Services Research
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Participants receive control message<br>Participants only receive standard heat risk warning | |
| Experimental: Participants receive intervention message<br>Participants receive standard heat risk warning plus figures incorporating the health impacts of heat and pro-environment behaviors. | Behavioral: Heat risk and pro-environment behavior message<br>* Eligible participants will be randomized to either a control condition to receive a standardized heat health warning or an intervention condition to receive a heat health warning plus figures depicting heat risk and pro-environment behavior via their preferred and accessible channel (WhatsApp, WeChat or the text message) each time when a Very Hot Weather Warning is issued by the Hong Kong Observatory.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Emotional engagement with heat and climate change risk (emotional valence) | Measure participants' emotional engagement with risk of heat stress and climate change, in specific, participants will be asked to indicate how they feel about the health impacts of climate change (using a slider from -3 to 3). Higher scores indicate more positive emotion. | One week after completion of all messages delivery | 
| Emotional engagement with heat and climate change risk (discrete emotion) | Participants will be asked how much they feel fear/helpless/worried/disgust when thinking about health impacts of climate change (on a 7-point Likert scale). Higher scores indicate stronger emotion arousal. | One week after completion of all messages delivery | 
| Short-term effect of risk perception toward heat and climate change risk | Their perceived health risk toward climate change and heat stress will be measured using items derived from our baseline and follow-up surveys (likelihood, severity and perceived worry will be used to gauge participants' risk perception). All measures on a 5-point likert scale with higher scores indicating greater risk perception. | One week after completion of all messages delivery | 
| Long-term effect of risk perception toward heat and climate change | Their perceived health risk toward climate change and heat stress will be measured using items derived from our baseline and follow-up surveys (likelihood, severity and perceived worry will be used to gauge participants' risk perception). All measures on a 5-point likert scale with higher scores indicating greater risk perception. | One month after completion of all messages delivery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Short-term effect of self-efficacy in taking pro-environment actions | Perceived self-efficacy in taking actions to mitigate climate change will be measured by four items derived from previous baseline and follow-up surveys.(Items include: 1) I can personally help to reduce climate change by changing my behavior 2) There are a variety of external factors that make it difficult for me to take actions that help to reduce climate change 3) My action to reduce the effects of climate change in my community will encourage others to reduce the effect of climate change through their own actions 4) If I want, it is easy for me to take actions to help tackle climate change). Responses will be rated on a 5-point Likert (Strongly disagree/Disagree/Agree/Strongly agree/No opinion). | One week after completion of all messages delivery | 
| Long-term effect of self-efficacy in taking pro-environment actions | Perceived self-efficacy in taking actions to mitigate climate change will be measured by four items derived from previous baseline and follow-up surveys.(Items include: 1) I can personally help to reduce climate change by changing my behavior 2) There are a variety of external factors that make it difficult for me to take actions that help to reduce climate change 3) My action to reduce the effects of climate change in my community will encourage others to reduce the effect of climate change through their own actions 4) If I want, it is easy for me to take actions to help tackle climate change). Responses will be rated on a 5-point Likert (Strongly disagree/Disagree/Agree/Strongly agree/No opinion). | One month after completion of all messages delivery | 
| Short-term effect of intention in taking pro-environment actions | Participants will also be asked to indicate their intention to 1) reduce energy waste 2) buy energy efficient products, and 3) change some of the daily habits to help tackle climate change. Responses will be rated on a 7-point Likert scale. Higher scores indicate greater behavioral intention. | One week after completion of all messages delivery | 
| Long-term effect of intention in taking pro-environment actions | Participants will also be asked to indicate their intention to 1) reduce energy waste 2) buy energy efficient products, and 3) change some of the daily habits to help tackle climate change. Responses will be rated on a 7-point Likert scale. Higher scores indicate greater behavioral intention. | One month after completion of all messages delivery |