Confusing association with causation - common journalistic pitfall - Gary Schwitzer's HealthNewsReview Blog

"We've just posted a new guide on the importance of the language used to describe the results of observational studies. Day after day we see stories that use active powerful verbs like "prevent...boost...lower your risk...may cut death rate" to describe the results of these studies. That's misleading and inaccurate because such studies can't prove cause-and-effect. Read more about why in this detailed, thoughtful piece by Mark Zweig, MD, and Emily DeVoto, PhD. (It's actually a revision of a piece these two wrote for us two years ago. The new one fits nicely in our "Tips for Understanding Studies" section.)"