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# How to read in a statistic whatever you want

It’s a common place that you can read nearly any result you want from a statistic. You just have to optimize your mathematical model or cut short the reasoning about the data. There is currently a JAMA publication from the American Medical Society which is cited in many magazines and newspapers (even in German Spiegel) as “22% less risk of colorectal cancer for vegetarians”. No ordinary reader of these reviews will have a look at the original numbers in the publication since it is not freely available (yet another reason for open Publication …). But here they are:

• Vegetarian participants: 40367
Cancer cases: 252
• Nonvegetarian participants: 37292
Cancer cases: 238

This makes for the following relative case numbers:

• Vegetarian: 0,624 / 100 participants
• Nonvegetarian: 0,638 / 100 participants

Or a difference of 0,014 cases per 100 people. This means, if you eat meat your risk to come down with a form of colorectal cancer increases by 0,014 percent. This reads quite different, doesn’t it?

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