[andruby]

Correct. The sample population was also limited. IIRC the main conclusion of the study is that larger scale studies should be conducted.

Every study has limitations. Do you feel that the limitations you stated mostly invalidate the study?

Nevertheless, like the professor of medicine at Harvard Medical School JoAnn Manson stated in May 2020 [0]: "The evidence is becoming quite compelling [that good Vitamin D status will protect against severe complications]".

[0] https://www.medscape.com/viewarticle/930152

[ekianjo]

Effect size matters as well, not just sample size. The effect size in this paper is huge.