Social determinants and drivers of use of SARS-CoV-2 self-tests in a French national cohort study

Abstract Background Self-tests for SARS-CoV-2 became quickly available after the onset of the epidemic. They were especially recommended for high-risk and hard-to-reach populations. This study examines whether self-tests successfully reached vulnerable groups during first months of availability in France. Methods The EpiCov study is a national population-based cohort study conducted in France during the Covid-19 pandemic. Primary outcome variable was use of self-test at last SARS-CoV-2 test, among those who reported testing at least once between May-July 2021. Univariate and multivariate binomial weighted logistic regressions were run, stratified by age group (16-24 yrs, 25-59, 60+), to identify social determinants and drivers of use of self-tests. Results Overall, 11% of the population who tested for SARS-CoV-2 between May-July 2021 reported using a self-test as last test. Demographic factors were highly predictive of use of self-tests among 25-59 y/o, but not among younger and older age groups. Use of self-tests was highest among 16-24 y/o, people with higher education, lowest population density areas, and people with high overall frequency of testing. Use was lowest among 60+ y/o, unemployed and retired people, and first-generation immigrants. When stratifying by age, 16-24 y/o with high perceived Covid-19 risk were more likely to use self-tests (aOR 1.99, 95% CI 1.10-3.59). Among 25-59 y/o, in-person workers were more likely to use self-tests than remote workers (aOR 1.91 [1.20-3.05]). Among 60+ y/o, employed people were more likely than retired people (aOR 3.97 [2.30-6.85]). Conclusions With higher utilization in low population density areas and among frequent testers, convenience may be a primary driver of use of self-tests. Additional drivers include perceived risk among younger people and exposure at work for those ≥25 yrs. Inequities in use were observed, with lower use among people with low education, older age, and immigrants. Key messages • Use of self-tests in France during the Covid-19 pandemic was low among vulnerable population groups, including people with lower education, immigrants, and older individuals. • Drivers of use included geographical access to healthcare services, perception of risk among younger respondents, and exposure at work among adults aged ≥25 years.