Cannabis use disorder and subsequent risk of depression and bipolar disorder
I can't see the full study methodology without an account. That said…<p>The challenge with running studies ethically is that you can't split your test groups into two groups and somehow induce cannabis use disorder and see if major depression, bipolar, etc results from it. Rather, you can see if the people who naturally develop the disorder also have those problems.<p>The flaw in this reasoning is that people who develop depression and similar issues are likely to self-medicate with cannabis. In related news, umbrellas do not cause rain.