Is it riskier to meet 100 people outdoors or 14 people indoors? Comparing public and expert perceptions of COVID-19 risk

Today,  Friday, 18 December 2020, we published the working paper “Is it riskier to meet 100 people outdoors or 14 people indoors? Comparing public and expert perceptions of COVID-19 risk.”

The risk of infection from COVID-19 in social settings depends on multiple factors, including how many people there are; whether they maintain social distance; whether they meet indoors or outdoors; how long they meet; and whether they wear masks. Combining these factors to judge the risk of infection in any one situation is difficult and could mean people underestimate or ignore some risk factors. This working paper presents an experiment undertaken by the ESRI’s Behavioural Research Unit (BRU) to measure how the public think about the risk of infection from COVID-19 in social settings, in research funded by the Department of Health to support the Behavioural Change Subgroup of the National Public Health Emergency Team (NPHET).

The multi-stage, interactive experiment recorded how a representative sample of 800 members of the public judged the risk of infection in different social settings and compared their judgements to those of a sample of medical experts (including members of NPHET’s Expert Advisory Group). The findings show that the public focus on how many people they come close to when thinking about risk and, compared to the medical experts, underestimate the benefits of meeting others outdoors rather than indoors. A final task in the experiment, completed only by members of the public, showed that when the risk of infection competed against a different type of risk (e.g. needing to use public transport to attend an important medical appointment) people thought the risk of contracting COVID-19 was lower.

Together, the findings imply that people may unknowingly place themselves in environments with higher risk of infection.