The sheer volume of medical information available now through the internet is overwhelming. However, one of the main challenges for the non-medical person encountering this abundance of information is not simply the amount of medical information currently available; its that the information is not provided in any easily understood context.
If you watch the teasers for the evening news, they invariably say, "XYZ...the New Crisis - are your kids safe?" XYZ being whatever big study finding just came out in the NEJM (New England Journal of Medicine) or JAMA (Journal of the American Medical Association). The article referenced above discusses this in terms of the "availability heuristic":
Basically, we judge the importance or likelihood of something happening by the ease of bringing instances of that thing to mind. So we tend to overestimate the probability of a rare risk that is seen in a news headline, because it is so easy to imagine. Likewise, we underestimate the probability of things occurring that don't happen to be in the news. A corollary of this phenomenon is that, if we're asked to think about a series of things, we overestimate the probability of the last thing thought about because it's more easily remembered.
And yet, despite all these "crises" we're living longer than ever. If these are "crises" then, please. Give me more crises. Apparently, they keep adding years to my life. To the point, newspapers and newscasters rarely put these studies in context. By context I mean:
- cumulative data: how do these results compare to previous studies?
- experimental design: are there flaws in any or all of the studies?
- power: did they have enough test subjects to achieve statistical significance?
- data comparison: how does this risk compare to the risk of getting bitten by a shark or hit by a bus?
Thus, people get understandably confused. Relying on sensationalistic media for their medical information, which seeks to grab your attention even more than it does to inform, in alternating years, coffee or salt or fat or whatever is either the greatest thing since My Little Pony or the worst since Thalidomide.
Another idea introduced by the article is the concept of "control bias" is another aspect of risk analysis that affects people's habits. People underestimate risk in situations where they have some measure of control, and overestimate risk when they don't have control. Many people fear flying, and yet they are approximately 2000 times more likely to die if they drove to Grandma's instead.
A book on this subject that I recommend for everyone is "The Science of Fear" by Daniel Gardner.