This study investigates the association between the use of renin–angiotensin–aldosterone system (RAAS) inhibitors and the risk of positive Covid-19 test results and severe Covid-19 outcomes among patients tested for Covid-19. The study included 12,594 patients, of whom 5894 (46.8%) tested positive for Covid-19, and 1002 (17.0%) had severe illness. The researchers used Bayesian methods and propensity-score matching to compare outcomes in patients who had been treated with RAAS inhibitors (ACE inhibitors, angiotensin-receptor blockers, beta-blockers, calcium-channel blockers, or thiazide diuretics) and those who were untreated. They found no substantial increase in the likelihood of a positive Covid-19 test or severe Covid-19 among patients who tested positive, regardless of their medication history. Specifically, there was no significant difference in the likelihood of a positive test or severe illness with at least 97.5% certainty for all medication classes. The study concludes that the use of RAAS inhibitors does not appear to increase the risk of Covid-19 or severe Covid-19 outcomes.This study investigates the association between the use of renin–angiotensin–aldosterone system (RAAS) inhibitors and the risk of positive Covid-19 test results and severe Covid-19 outcomes among patients tested for Covid-19. The study included 12,594 patients, of whom 5894 (46.8%) tested positive for Covid-19, and 1002 (17.0%) had severe illness. The researchers used Bayesian methods and propensity-score matching to compare outcomes in patients who had been treated with RAAS inhibitors (ACE inhibitors, angiotensin-receptor blockers, beta-blockers, calcium-channel blockers, or thiazide diuretics) and those who were untreated. They found no substantial increase in the likelihood of a positive Covid-19 test or severe Covid-19 among patients who tested positive, regardless of their medication history. Specifically, there was no significant difference in the likelihood of a positive test or severe illness with at least 97.5% certainty for all medication classes. The study concludes that the use of RAAS inhibitors does not appear to increase the risk of Covid-19 or severe Covid-19 outcomes.