A large-scale genome-wide association study meta-analysis of cannabis use disorder.

[NNadir]

6. Well, of course, you are entitled to the opinion that no one anywhere at any time should publish...

...meta analysis or reviews, because, um, they don't stand up to cursory reads but nevertheless the world scientific community, despite your objections based on your treatment of patients, seems to disagree.

So do I.

You can write to Lancet Psychiatry if you wish to suggest a retraction of the paper on the grounds that meta analyses are garbage, but I don't think the majority of the authors - and there are many - will agree to your objection.