I didn't see anything wrong with the study per say. They made an objective observation, unequivocally stated that weed may or may not be the cause beyond the increased rate of psychosis, and then stated that in their best opinion it is probably marijuana.

They probably have more reasons underlying this opinion. If what they had on msnbc is all the researchers had behind their claim, then yes, it's probably stupid, but my guess is that this article is a severely abridged version of the actual study that was published. Msnbc is not going to get into the nitty gritty scientific details.

And even if the study is accurate, so what? People do stuff all the time that is harmful for them. Alcohol damages your liver. It's probably still worse for your health than pot. Same with cigs. I don't understand why the government has a war against pot.

What would be bad is various agencies trying to mislead people based on this study. This study itself seems alright to me.