Investment tips are fun. You can swap them with friends, and hopefully make a couple grands. At a book store, you are likely to pick an investment tycoon's recent book, maybe learn a few tricks. Health risk information, on the other hand, is anything but cool. On the other hand, the stakes are a lot higher.
"Colon cancer will strike about 150,000 Americans" is alarming in and of itself. Now try combining it with the statement "The early warning signs of colon cancer: You feel great. You have a healthy appetite. You're only 50." If you happen to be 50 and healthy, you're probably sweating by now, certain you're going to get it. ‘It' being colon cancer, because it will strike so many Americans and you, for one, are displaying the early symptoms.
Should you be breaking a cold sweat? Writing a will? Asking more questions? And just what should those questions be?
The first step to tackling health messages such as the ones above, is to get at the bottom of the statistical information these messages convey. You need to ask: "150,000 out of how many?" True, 150,000 is a lot of people, but, keeping in mind that there are 300 million Americans, the ones diagnosed with colon cancer constitute a small proportion of .05%. In other words, 5 out of every 10,000 Americans will be struck by colon cancer. This is not exactly good news, especially not for those five, but it suddenly seems less devastating.
Three MDs, Steve Woloshin, Lisa Schwartz, and Gilbert Welch, recently published "Know your chances: understanding health statistics" http://www.ucpress.edu/books/pages/10893.php It's a book that helps you determine whether you should be writing that will. The authors show how to disintegrate the deceptively simple messages above to questions such as: does every American over 50 who feels great and has a healthy appetite have colon cancer? And what exactly is ‘struck'? Because developing colon cancer is not the same as dying from it.
And nothing is straightforward as it seems. An ad promising 42% reduction in deaths from heart attack will make most of us take the medication. Especially when looking at the picture of a loving mid-life couple. They're both smiling, and you just know he'll take the medication so as to have more good years with her. Obviously, the benefit is big, right? Because reducing a risk by 42% is cutting is almost in half. Except we do not know a half of what we are reducing. There is virtually no way of knowing what the base rate risk is. And we may ignore this fact, unless we educate ourselves in health statistics.
Like casino décor, health messages do not come out of nowhere. They have a clear and deliberate design. Every one of the opening messages is true: colon cancer will strike 150,000 Americans, .05% of Americans, and 5 out of every 10,000 Americans. Yet which one would you choose to use if, instead of an unsuspecting patient, you were a pharmaceutical company, an advertiser, or a lobbyist soliciting money for your organization? Reading the book helps you realize you cannot afford to be unsuspecting, not when your health is at stake. The only way to read through their agenda is by educating ourselves in the ins and outs of information presentation. A practice well worth the two hours it will take you to get through the book and achieve ‘healthy skepticism', which is what these good doctors prescribe. Probably not too bad to exercise when investing either. I am sure Mr. Buffet would approve.
