Starting Risk
(With “placebo” book)
Modified Risk
(With our book)
Did our book help?
Lecture series trial
   Got a passing grade on test56%74%
   Got an A on test7%26%
VA trial
   Got a passing grade on test26%44%
   Got an A on test2%10%
Did our book have side effects?None reported

From: Chapter 9, Beware of Exaggerated Certainty

Cover of Know Your Chances
Know Your Chances: Understanding Health Statistics.
Woloshin S, Schwartz LM, Welch HG.
Berkeley (CA): University of California Press; 2008.
Copyright © 2008, The Regents of the University of California.

Know Your Chances: Understanding Health Statistics is hereby licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported license, which permits copying, distribution, and transmission of the work, provided the original work is properly cited, not used for commercial purposes, nor is altered or transformed.

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