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The Effect of a Deliberation-Prompting Intervention in Voluntary Social Distancing
Initial registration date
July 01, 2020
July 02, 2020 1:44 PM EDT
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Erasmus University Rotterdam/Tinbergen Institute
Other Primary Investigator(s)
Additional Trial Information
Existing research findings have shown that voluntary social distancing is a vital element of containing the spread of the coronavirus. When countries start to gradually relax lock-down measures, it is important for the policy makers to consider that individuals’ voluntary social distancing would be beneficial for the society. However, when lock-downs are relaxed there are strong signals which may work against voluntary social distancing. The relaxation of measures may send out a public signal for less alertness, which may also lead to declining compliance to the governmental guidelines. With such policy conundrum, is it possible to promote social distancing by nudging people to deliberate on the consequences of behaviors? This study investigates the effect of a deliberation-prompting intervention in encouraging voluntary social distancing. A randomized experiment will be conducted among the general public in the UK, comparing the deliberation-prompting intervention with a standard information message intervention, as well with a control group with no intervention.
The experiment consists of two treated groups (information message, information message + deliberation-prompting intervention) and one control group.
Intervention Start Date
Intervention End Date
Primary Outcomes (end points)
1) behavior intentions on the number of social activities, the number of shop visits and the extent of complying to the one meter plus social distance in the next week.
2) interests in learning about how to avoid crowds.
3) self-reported behavior (from a week later) on the number of social activities, the number of shop visits and the extent of complying to the one meter plus social distance.
Primary Outcomes (explanation)
Secondary Outcomes (end points)
Secondary Outcomes (explanation)
The experiment consists of two parts. In part I, subjects are randomly assigned into one of the treated groups or the control group. Immediately after the intervention, some behavior outcomes are elicited. Part II takes place one week after part I. During part II, subjects report their behavior and beliefs.
Experimental Design Details
Randomization will be done by the build-in function of Qualtrics
The unit of randomization is individual.
Was the treatment clustered?
Sample size: planned number of clusters
Sample size: planned number of observations
780 individuals are aimed for the completion of the first survey; the number of individuals following up in the second survey would depend on attrition.
Sample size (or number of clusters) by treatment arms
The following sample size is aimed for the completion of the first survey:
260 for the control group, 260 individuals for the information message, 260 individuals for information + deliberation intervention.
The sample size of the second survey would depend on how many subjects would follow up.
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
INSTITUTIONAL REVIEW BOARDS (IRBs)
the Internal Review Board, section experimental research, of the Erasumus School of Economics, Erasmus University Rotterdam
IRB Approval Date
IRB Approval Number
ESE IRB-E Application 2020-04