If cannabis is getting stronger, why aren't cases of schizophrenia rising?

It remains contested whether a cause-and-effect relationship between smoking cannabis and schizophrenia truly exists
The Conversation (UK)
Friday, March 23, 2018

Most people who smoke pot enjoy it, but a smaller proportion experience psychotic-like symptoms, such as feeling suspicious or paranoid. The question that polarises researchers is whether smoking cannabis is associated with a risk of developing psychotic problems, such as schizophrenia, in the long term. Of course, cannabis use is common, while schizophrenia is relatively rare, affecting less than one per cent of the population. Even if cannabis use were to double the risk, over 98% of cannabis users would not develop schizophrenia. Researchers have to tread carefully in evaluating the evidence and avoiding scaremongering. (See also: How we could make cannabis safer for users)