Wednesday, January 13, 2016

Correlation is not causation

Don't jump--or in this case, stand--to conclusions. Oh, and have I mentioned I have a standing desk? (And what the heck is adiposity?) From The Daily Beast.

Does Standing Lead to Weight Loss?
The Washington Post told readers that “standing for at least a quarter of the day reduces odds of obesity.” 
Inside the article, it was reported that the benefit of such standing is immense, with the smallest effect size at 32 percent. The analysis apparently found that men who said they stand a quarter of the time were 32 percent less likely to be obese than those who said they don’t stand at all. 
If we were to take such a claim seriously, it would have been impossible to explain how obesity had become so widespread, as its curtailment should have been as easy as giving away some standing desks.

Of course, in the cited study, recently appearing in Mayo Clinic Proceedings, the authors appropriately drew a more modest conclusion that “standing more than a quarter of the time is related to reduced odds of elevated adiposity.” (Our italics.) The switch from “is related to reduced odds” in the research paper to “reduces odds” in the news headline changed the meaning entirely, inserting a cause-effect relationship that has not been proven in neither the present study nor other studies.

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