“…The main quality issue noticed in 14 studies [35,40,52,59,61,63,66,74,78,80,84,89,90,92] was the comparison of cohorts with inadequate adjustment for confounders that may influence the estimated risk of severe/critical disease associated with the use of ACEIs/ARBs. Another major issue detected during quality assessment in 12 studies [35,52,59,61,66,74,75,78,80,84,90,92] was the inability to ascertain the exposure to ACEIs/ARBs during the course of illness, where the possibility of discontinuation of ACEIs/ARBs upon COVID-19 diagnosis could not be ruled out based on the study design. Similarly, 12 studies [40,52,59,61,63,74,75,78,84,89,90,92] were not able to demonstrate that severe/critical outcome was not present at the start of the study based on their study design.…”