Air pollution perceptions and behavior in the UK

Last registered on November 17, 2023

Pre-Trial

Trial Information

General Information

Title
Air pollution perceptions and behavior in the UK
RCT ID
AEARCTR-0008352
Initial registration date
October 14, 2021

Initial registration date is when the trial was registered.

It corresponds to when the registration was submitted to the Registry to be reviewed for publication.

First published
October 15, 2021, 5:38 PM EDT

First published corresponds to when the trial was first made public on the Registry after being reviewed.

Last updated
November 17, 2023, 9:21 AM EST

Last updated is the most recent time when changes to the trial's registration were published.

Locations

Primary Investigator

Affiliation
Grantham Research Institute, London School of Economics

Other Primary Investigator(s)

PI Affiliation
London School of Economics and Political Science
PI Affiliation
London School of Economics and Political Science
PI Affiliation
London School of Economics and Political Science

Additional Trial Information

Status
Completed
Start date
2021-09-24
End date
2021-12-07
Secondary IDs
Prior work
This trial does not extend or rely on any prior RCTs.
Abstract
This study will undertake an analysis of the relationship between perceived and estimated air pollution exposure, risk perception and behaviour. The overarching aim of the study is to explore dimensions of vulnerability and how they link to awareness, perceptions and behaviour. We aim to describe the overlapping dimensions of vulnerability (susceptibility, exposure and adaptation); quantify where there are gaps in awareness, perceptions, and behaviours in relation to air pollution exposure and avoidance; and whether these vary by vulnerability status. We will also examine the extent to which perception differs from actual exposure and the heterogeneity of this outcome by domain (within the home, local area and commute) and the vulnerability status of the respondent (age, health morbidities and status).
External Link(s)

Registration Citation

Citation
McCoy, Daire et al. 2023. "Air pollution perceptions and behavior in the UK." AEA RCT Registry. November 17. https://doi.org/10.1257/rct.8352-1.1
Sponsors & Partners

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Experimental Details

Interventions

Intervention(s)
Information and feedback on actual air pollution exposure levels in a reference area.
Intervention Start Date
2021-10-04
Intervention End Date
2021-10-31

Primary Outcomes

Primary Outcomes (end points)
Perceived exposure and psychological factors related to risk and worry about air pollution
Primary Outcomes (explanation)

Secondary Outcomes

Secondary Outcomes (end points)
Behaviors relevant to air pollution exposure including location and dwelling characteristics, travel and outdoor behavior, heating sources and frequency, cooking sources and frequency.
Secondary Outcomes (explanation)

Experimental Design

Experimental Design
Random provision of information and feedback regarding reference levels of air pollution exposure.
Experimental Design Details
We randomize whether survey respondents receive information about air pollution levels in a reference area in the form of feedback on the accuracy of their perception of air pollution exposure in the reference area. This feedback is designed to test whether revealed inaccuracies (if any) regarding air pollution exposure levels are driven by unfamiliarity with the response scale (DAQI) or due to misperceptions about air pollution exposure. Comparing treatment and control groups, we will test the following (confirmatory) hypotheses:
• H1a: Providing feedback and information about actual levels of air pollution in the general area (Greater London and West Midlands for London and Birmingham surveys, respectively) affects perceived air pollution exposure.
• H1b: Providing feedback and information about actual levels of air pollution in the general area (Greater London and West Midlands for London and Birmingham surveys, respectively) reduces differences between perceived and actual air pollution exposure.
Randomization Method
Randomization done through embedded data in Qualtrics' survey platform
Randomization Unit
Individual
Was the treatment clustered?
No

Experiment Characteristics

Sample size: planned number of clusters
1,100
Sample size: planned number of observations
1,100
Sample size (or number of clusters) by treatment arms
750 control, 750 treatment
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
Power calculations for testing Hypotheses 1a and 1b above are based on pilot data collected in London. We use the average of perceived DAQI (4.46) and standard deviation of perceived DAQI (2.23) from the pilot data. We assume that our final sample size will be approximately 1,100 when combining surveys in London and Birmingham. At a 10% level of significance and 80% statistical power, we have a minimum detectable effect size of -0.3346 which is approximately 15% of the standard deviation of the outcome. This calculation is performed using the following code in Stata version 15: power twomeans 4.46, sd(2.23) alpha(0.10) power(0.8) n(1100) direction(lower)
Supporting Documents and Materials

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IRB

Institutional Review Boards (IRBs)

IRB Name
Research Ethics, London School of Economics and Political Science
IRB Approval Date
2021-07-16
IRB Approval Number
N/A
Analysis Plan

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Post-Trial

Post Trial Information

Study Withdrawal

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Intervention

Is the intervention completed?
Yes
Intervention Completion Date
December 07, 2021, 12:00 +00:00
Data Collection Complete
Yes
Data Collection Completion Date
December 07, 2021, 12:00 +00:00
Final Sample Size: Number of Clusters (Unit of Randomization)
2821
Was attrition correlated with treatment status?
Final Sample Size: Total Number of Observations
2821
Final Sample Size (or Number of Clusters) by Treatment Arms
931 in control, 1890 in treatment
Data Publication

Data Publication

Is public data available?
No

Program Files

Program Files
No
Reports, Papers & Other Materials

Relevant Paper(s)

Reports & Other Materials