Every day we're bombarded with news stories about our growing risk for getting this or that. If you eat fish you have a 30% greater chance of getting something or other, and if you drink three cups of coffee a day you have a 40% of not getting some disease or condition. Pretty soon it's all background noise.
There are some basic things you really should know so you'll be better able to judge whether the news, a magazine story or a recommendation from your healthcare provider should indeed get your attention.
It's important that you understand enough about what all these percentages mean when you're faced with a key decision, such as whether to have surgery or pass on the option, or whether an invasive test or procedure is worth the risk.
Here's a good example. Research last year discovered that women who had migraines had a 40% greater chance of getting multiple sclerosis than did women without those headaches. That sounds pretty worrisome.
But the fact is, the chance of getting multiple sclerosis for a woman who suffers from migraines is less than 1 in 100 (0.47%). For women without migraines, it's also about 1 in 100 (0.32%). So not to worry. But that 40% worse statistic probably made a lot of people concerned.
When you're faced with a healthcare decision -- Should I have the surgery? Should I take statins? Do I need an annual mammogram?' -- ask for the hard numbers and then explore what the data really means. For example:
- If you are told that a drug, treatment, procedure or surgery would reduce your chance of a problem by a certain percent, ask what your chance of the problem would be without it
- Be wary of any numbers that involve what is called "relative change" -- in other words, remember that a 40% increase of a tiny number is still very small.
- Ask your physician to outline the possible benefits and downsides given your particular profile -- your age, risk factors, family history, life style -- in clear terms.
- Question the source of the numbers. Is this from just one study? How many people were involved? Or is it from a large amount of research? Was the research published in a peer-reviewed journal, a place where other experts weigh in on its value? Who funded the research?
Know that numbers are often used because of their potential power, but they can be selected -- on purpose or inadvertently -- to confuse. Numbers are' often used to persuade you to do something.
The better you are at discerning the truth, the healthier you're likely to be.