that’s not any kind of proper scientific study.
It actually is. Here's the link to the study.
https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)31180-6/fulltext
https://en.m.wikipedia.org/wiki/The_Lancet
"The Lancet is a weekly peer-reviewed general medical journal. It is among the world's oldest and best-known general medical journals"
Journal impact factor of 59 is crazy high, far higher than any scientific journal I've published in.