They've not shown that dope smoking makes you mad, no they haven't

Much shouting is about to happen as a report claims that smoking cannabis causes schizophrenia. Which isn’t what has been shown or proven at all - that is what has been assumed.

The Telegraph:

Almost a third of schizophrenia cases in young men triggered by cannabis use

One stage back is the NIH:

Young men with cannabis (marijuana) use disorder have an increased risk of developing schizophrenia,

That’s already a step back in the claim. And the actual paper itself:

At a population level, assuming causality, one-fifth of cases of schizophrenia among young males might be prevented by averting CUD.

We’ve long known that there’s a correlation with heavy dope smoking and getting schizophrenia. The bit we don’t know is whether those feeling the madness descend self-treat with lots of dope or whether the dope causes the descent of the madness.

There will be a lot of people shouting about this report, shouting that it proves the movement is from dope to mad. Which isn’t what was shown at all, that is what was assumed.

Science is, of course, a public good, it’s even good for the public. But it is necessary to just check what is actually being said by the science. This paper measures the size of the correlation between cannabis and schizophrenia. It doesn’t even attempt to decide upon the causality. Despite what varied prodnoses are going to shout at us.