Prospective survey-based study with 15,227 people in the UK, showing lower risk of COVID-19 cases with vitamin A, vitamin D, zinc, selenium, probiotics, and inhaled corticosteroids; and higher risk with metformin and vitamin C. Statistical significance was not reached for any of these. Except for vitamin D, the results for treatments we follow were only adjusted for age, sex, duration of participation, and test frequency. NCT04330599
. COVIDENCE UK.
risk of case, 6.8% lower, RR 0.93, p = 0.53, treatment 141 of 5,640 (2.5%), control 305 of 9,587 (3.2%), NNT 147, adjusted per study, odds ratio converted to relative risk, fully adjusted, group sizes approximated.
Effect extraction follows pre-specified rules prioritizing more serious outcomes.
This study is excluded in the after exclusion results of meta
significant unadjusted confounding possible.
Holt et al., 3/30/2021, prospective, United Kingdom, Europe, peer-reviewed, 34 authors, study period 1 May, 2020 - 5 February, 2021, dosage not specified.