Know Your Chances: Understanding Health Statistics

Discussions of health care reform tend to focus on who pays for care. This book is a much-needed reminder to address an even more important question: Why are we struggling to pay for treatments and drugs that may not be accomplishing anything? The authors walk us through a discussion of risk with detailed examples and illustrations. Sure, it's a little simple, but not everyone has studied statistics. I've had graduate-level stats courses and I found the discussions helpful and enlightening. What's really scary is that we're exposed to hype in news reports, which often seem to come directly from press releases of the pharmaceutical companies. I wonder how many MDs read these statistics without understanding what's going on. Even worse, we're getting propaganda from medical institutions. The authors show a misleading flyer from the prestigious M.D. Anderson Health Center in Houston. My favorite part of the book is the discussion on survival rates. If you're diagnosed early you may not get an extra day of life. You just live with the knowledge longer. I can't help wondering if the millions of dollars we're spending on drugs claiming to lower cholesterol and reduce hypertension might not be better spent on healthy food, exercise and stress reduction. As the authors point out, we need evidence that people with better "numbers" really live longer and experience less suffering. We also need evidence that these drugs really contribute to meaningful outcomes, not just lower numbers. Just this morning the Wall Street Journal solemnly reported a drug that promised to lower "prostate cancer risk" by 23% among a large sample of high-risk men. Following the guidelines of this book, it was easy to spot flaws. The difference between the placebo group and the drug group was just 6.5%, not 23%. In other words, out of 1000 men, 65 seem to have been spared the diagnosis - not 230. Is that a big number? The authors advise, "It's up to you." The authors warn us to look with skepticism at promised outcomes. For instance, "shrink the tumor" doesn't always mean "reduce risk death by cancer." "Increase bone density" doesn't mean "avoid hip-fracturing falls." In this article, the outcome was "diagnosed with prostate cancer," not "death from prostate cancer." If many of the men were 70 or over, it's possible that they would end up dying *with* prostate cancer, as opposed to dying *from* prostate cancer. The only point I'd add (and I may have missed it in the book) is that extremely large samples can lead to misleading results. When you have huge samples, you can get significant correlations by chance. A study of hundreds of thousands sounds impressive but you need to look more closely. Everyone needs to read this book, especially consumers of the medical system, legislators and regulators.

This book is absolutely superb! The authors do an excellent job in bringing the often complicated field of medical statistics to a level that any interested layperson can easily understand. In addition to going through many examples that illustrate how important it is to ask the right questions when confronted with often sketchy statements about survival rates, death rates, drug performances, etc., they show how useful information may be sought and interpreted. This information may then be used by the interested individuals to make decisions about what to do in their own specific cases. The book includes a glossary, risk charts for women and men (with information on how to read them) and many other useful features. The writing style is clear, friendly, engaging and authoritative while remaining jargon-free. Because of this, the book is accessible to a very broad readership. In addition, this book can be considered as another important contribution to the fight against innumeracy. It can be enjoyed and used by anyone.

If I were in charge of store displays, I would require that this book would be prominently presented for sale next to every pharmacy in this country. And I would recommend that every person who takes any medicine read it. This book is a terrific, easy to read resource for anyone who wants to make truly informed decisions regarding the risks and benefits of their personal health situation. In this technologically sophisticated age, we want to believe that those highly marketed drugs improve our health - both when we are sick and when we are trying to prevent disease. As a genetic counselor who works with families who have an increased risk of developing cancers, I spend much of my clinical time helping them understand their risk of disease and management options to reduce that risk. Many procedures and drugs do help certain people, but this book will help you understand if the drug or procedure will make a significant difference - or if you (or your third party payor) will be spending lots of money for only a little benefit. In addition, as our country continues to deal with a health care system that desperately needs to be fixed, this primer will be important for everyone who participates in the policy conversations to gain a better understanding of the way in which hype about medical risks and benefits often confuses the discussion.

When we are barraged with drug ads that promise miracle cures to our everyday life problems, when there's a good chance our doctor is on the payroll of a drug company, and when patient advocacy organizations are often funded by the pharmaceutical industry, it's hard to know what medical information to trust. "Know Your Chances" is a clearly-written and easy-to-understand guide that helps the reader to figure out fact from fiction in medical information. The authors are well-known doctors from Dartmouth Medical School who have spent many years analyzing and teaching about risk analysis in medicine. They bring their teaching ability to this book - presenting engaging examples and easy to learn tools for deciphering medical statistics. This is a book everyone should read to ensure that they are getting the best health information possible.

As the medical care industry consumes larger proportions of the U.S. GDP we are bombarded by a rising number of messages from pharmaceutical companies,medical device suppliers, hospitals, medical specialists and activists seeking attention for their medical services and causes. Adding to these advertisements are medical reporters trying to attract eyeballs to their print or electronic news media. Often these messages are accompanied by numbers intended to cast an amplifying light onto the message or simply parroted by "health reporters" too lazy to interpret data into a less misleading or alarmist form. Know Your Chances: Understanding Health Statistics is a fast read, only 113 pages, that takes the reader step by step through what it takes to put these numbers into perspective. Why, for example is it true that the risk for being struck with colon cancer is both 5 out of 10000 and 1 out of 19. The difference between the two is time frame which is often omitted from the message. Naked percentages are another abuse of numbers often appearing in messages. Activists will often use large percentages of small populations to suggest a big change while a corporation might use a small percentage of a large population to play down danger. Both are misleading but common. The authors define risk in the first chapter and show the reader how to put it into perspective in chapters 2 and 3. This foundation is important as it shows how the oft cited lifetime population or annual population risk is not the same as individual risk. Lifestyle, family and medical history greatly influence individual risk. The benefits of "health intervention" are tackled in chapters 4 and 5. Aside from weighing the benefits of intervention against the risk of doing nothing side effects must be considered. Also the outcome of an intervention must be distinguished from a treatment's benefit. They're not the same. Think reducing risk is always good? Think again. Reducing a minor risk with a treatment that has dangerous side effects is hardly desirable. Think about a sleeping pill that might gain you 30 minutes more sleep during an eight hour night but leave you feeling drowsy during your morning commute. Chapters 6 and 7 educate the reader about the downsides of risk reduction and how to balance benefit against side effects. The remaining chapters show help the reader recognize exaggerated claims and how to become a healthy skeptic. Each chapter includes simple but illustrative quizzes that help the reader ensure they have grasped the concepts discussed. This book will likely be read by few patients. Few know about the book and most simply follow their doctor's advice. However this book should be a must read for any health reporter. Policy makers and influencers hoping to improve the quality of health care would also benefit reading this book.Primary care doctors would also benefit with a gentle reminder of what the learned or should have learned in medical especially in a