Observational study miscommunication of the week: citrus & stroke

Health News Review:  by Gary Schwitzer – February 24, 2012.

A spin around the Web today will give you many stories about citrus fruits and women’s stroke risk.

• Citrus Fruits May Lower Women’s Stroke Risk – WebMD
• But in the body of the story there’s not a word about the limitations of such an observational study.  Only this quote: “Our study supports the conclusion that flavanones are associated with a modest reduction in stroke risk,” says researcher Kathryn M. Rexrode, MD, MPH, of Boston’s Harvard Medical School and Brigham and Women’s Hospital.  Associated with does not = “lower women’s stroke risk.” Association ≠ causation.

It got worse.

• Credit: http://www.sxc.hu/profile/redzonk

  An Orange A Day Keeps Stroke Away –MedPage Today

• Somebody at the usually-exemplary MPT went nuts with that headline and it belies the caution exercised in the body of the article.  “Observational study” was mentioned in the lead sentence.  Read more