I did exactly the same and went to leave a comment saying as much and saw this. I hoped that the article itself would make at least some attempt to deal with t

I did exactly the same and went to leave a comment saying as much and saw this. I hoped that the article itself would make at least some attempt to deal with the issue, but it does not. It’s a meta study (meta meat?) that includes a set of studies. Those studies do not randomly assign people to eat/abstain from meat. It’s as bad as it sounds. Further, they use their poor study to criticise other, poorer, studies.