Fig. 2
![Fig. 2](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs12937-021-00744-y/MediaObjects/12937_2021_744_Fig2_HTML.png)
Forest plot showing the association between serum vitamin D level and risk of COVID-19 infection and death in patients with COVID-19. A-B: COVID-19 infection, vitamin D was analyzed as a categorical variable (A: upper) or continuous variable (B: lower). C-D: Death, vitamin D was analyzed as a categorical variable (C: upper) or continuous variable (D: lower). (Continuous variable: vitamin D per 10 ng/ml increase). Abbreviations: COVID-19, coronavirus disease 2019; OR, odds ratio; CI, confidence interval; IV, inverse variance; SE, standard error