As part of the Phase 3: Asbestos National Strategic Plan 2024-2030 (ANSP), the Asbestos and Silica Safety and Eradication Agency (ASSEA) aims to encourage the safe removal of asbestos from Australian residences.
For residential buildings, the cost of asbestos removal, disposal and replacement is the main impediment to removal (Ipsos 2018). Hypothetical government initiatives that reduced this cost for homeowners (e.g. subsidised removal or disposal, low or no interest loans, and tax concessions) have been associated with higher reported willingness to remove asbestos (Ipsos 2018).
This research will test the impact that information about the increasing risk of asbestos (due to its increasing age) can have on the amount participants are willing to pay to remove asbestos (Randomised Controlled Trial).
ADDITIONAL TRIAL INFORMATION
Intervention start and end date: Thursday, 5th September 2024 to Thursday, 26 November 2024
Ethics approval: Human Research Ethics Committee (HREC) Humanities and Social Sciences, Macquarie University. Reference: 520241809158945, Project ID: 18091
Experimental design including randomisation: This research consists of one 2-arm randomised controlled trial embedded in a survey delivered online using the Qualtrics platform. Participants will be randomised to 1 of 2 arms. Randomisation will be done by Qualtrics, by giving each participant a 1/2 probability of being assigned to each trial arm.
Intervention(s): The intervention is a short paragraph describing the increasing risk of asbestos in Australian homes. The treatment/intervention group receive this information before being asked to complete the outcome measure. The control group receive the same information only at the end of the study (after completing the outcome measure).
Control condition: The control group receive the same information only at the end of the study (after completing the outcome measure).
Outcome(s): The primary outcome measure is the price (in $) participants say they could afford to pay if they had to remove asbestos. At the individual level this is asked as a single question, and participants enter a dollar value in response. At a group level this will be the mean dollar value in each group.
Expected sample size: Our sample is fixed at around 4,500 individuals, which will provide 2,000 individuals per group (conservatively, after exclusions).
Minimum detectable effect size for main outcomes
For this study, alpha is set to 0.05, and hypothesis tests will be two-sided. Our pilot study revealed a much larger SD in the outcome variable than initially assumed (SD = $28,599). With this variability incorporated, we calculated the design has 80% power to detect an effect size of $1740 (Cohen’s d = 0.061).
Other: AEA pre-registration: TBA