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Individual health risks and policy preferences during a pandemic: evidence from El Salvador
Initial registration date
June 03, 2020
July 02, 2020 3:08 PM EDT
Other Primary Investigator(s)
Erasmus School of Economics
Additional Trial Information
In response to the covid19 crisis, El Salvador has imposed one of the strictest lockdown policies. The severe restrictions imposed create specific challenges and costs for poorer populations. As many rely on informal work to survive, they may no longer earn an income and are at risk of falling further into poverty. At the same time, these populations may have many health problems that increase their probability of developing severe symptoms if they contract covid19. Hence the extent to which individuals support alternative policy measures may depend on their health risk perceptions, which themselves may be based on imperfect knowledge. In this study, we follow up a cohort of clients from a micro-finance organization and test whether, upon receiving information about risk factors associated with serious cases of covid19, individuals update the perception of their own risks, and subsequently their policy support for alternative policies.
Lagarde, Mylene and Carlos Riumallo Herl. 2020. "Individual health risks and policy preferences during a pandemic: evidence from El Salvador." AEA RCT Registry. July 02.
To assess the effects of knowledge of risk factors for covid19 on risk perceptions and policy preferences, we will randomise individuals to one of three groups:
- A 'general information' group who will receive information about the main known risk factors of covid19 ;
- An ‘individualized information' group who will receive information about the number of known risk factors of covid19 they personally have;
- A control group who will receive no information.
Intervention Start Date
Intervention End Date
Primary Outcomes (end points)
Two main series outcomes:
(1) individuals' perceived probabilities of developing severe symptoms and dying from covid19
(2) individuals' support for protective measures to limit the spread of the virus
Primary Outcomes (explanation)
Secondary Outcomes (end points)
Secondary Outcomes (explanation)
The experiment will be conducted during a phone interview, realized in June-July2020 in San Salvador, the capital city of El Salvador. Study participants are a randomly chosen sub-sample of an existing study involving clients of a microfinance institution. Individuals have already shared their contact details and will be reached for a short telephonic interview.
Individuals will be randomised to one of the three groups before the interview. To ensure a high degree of balance and obtain the desired proportions across treatment groups within each stratum, we stratify the randomisation by income, known risk factors for covid19 and perceptions of health risk for covid19 (as elicited in March 2020).
Experimental Design Details
Randomization done in the office by a computer software programme
Randomisation will be done at the level of individuals.
Was the treatment clustered?
Sample size: planned number of clusters
Sample size: planned number of observations
Sample size (or number of clusters) by treatment arms
560 individuals in each arm
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
INSTITUTIONAL REVIEW BOARDS (IRBs)
London School of Economics
IRB Approval Date