Table 1 The general characteristics of the included studies
From: Zinc supplementation and COVID-19 mortality: a meta-analysis
Study | Country | Number of participants (case/control) | Study design | Age in years, mean (case/control) |
|---|---|---|---|---|
Yao [16] | USA | 196/46 | Observational study | 65/71 |
Carlucci et al. [13] | USA | 411/521 | Retrospective observational study | 63.19/61.83 |
Abd-Elsalam et al. [12] | Egypt | 96/95 | Randomized controlled study | 43.48/43.64 |
Thomas et al. [15] | USA | 58/50 | Randomized clinical open-label trial | 44.1/42 |
Patel et al. [14) | Australia | 15/18 | Randomized controlled trial | 59.8/63.8 |