The article attached below is a prime example of how the media fails to follow certain principles of scientific thinking. It claims that the use of marijuana in teens leads to depression and mental disorders later on in life. The article confuses correlation with causation by saying kids who smoke marijuana frequently are more likely to have depression including suicidal thoughts and lack of personal hygiene. They assume that because there is a relationship between the two observations they must be caused by each other; however, as the Marijuana Policy Project states in the article, they are not convinced there is a causal relationship. Instead, there could be a third variable such as the environment the teens are growing up in. If they live in a place that is discouraging, they may become depressed and turn toward marijuana as a way to fit in with their peers. It could also be that depression is actually the cause for teens to smoke rather than the other way around. Without doing further experimentations and observations the true relationship will remain a secret.
This article is a perfect example of how the media often confuses correlation with causation. It is very important to look at the news through the eyes of a psychologist. We must look at the factors that have been observed as well as how the article backs up its claim.