So, in the case where there’s no causal relationship, we’d expect to see about 22,320 people in the US who both used MDMA in the last year and are schizophrenic (3,100,000 MDMA users * 0.72%)
Given that there doesn’t seem to be a population-level study on this and the prevalence can explained without positing a causal relationship (definitely could find 32 folks at treatment centers out of 22,000), I think assuming causality here is a stretch.
Thanks, I didn’t find that study during my quick look.
I think this is a base-rates thing:
In the US, overall prevalence of schizophrenia is something like 7.2 people out of 1,000
In the US, around 3.1 million people use MDMA each year (In 2013, 1% tried in the last year * 2013 population of 316 million)
So, in the case where there’s no causal relationship, we’d expect to see about 22,320 people in the US who both used MDMA in the last year and are schizophrenic (3,100,000 MDMA users * 0.72%)
Given that there doesn’t seem to be a population-level study on this and the prevalence can explained without positing a causal relationship (definitely could find 32 folks at treatment centers out of 22,000), I think assuming causality here is a stretch.