Last week, the American Cancer Society issued a statement clarifying its position on routine cancer screening. Upholding its existing guidelines for early detection, it affirmed that many cancer screening tests are proven to save lives, but that cancer screening is not perfect: “Sometimes cancers get overlooked. Sometimes cancers get misdiagnosed. Sometimes aggressive cancers can appear even after a clear screening test. It is important to acknowledge these limitations, understand them, discuss them with your doctor, and decide what is right for you,” it said.

6a00d83453e6e169e20120a6263c23970b-120wiCancer is complicated, and there are no simple answers–the decision to screen or not to screen depends on many factors, and ultimately lies with the individual and his or her doctor. Challenging the idea that more testing is always better, H. Gilbert Welch (pictured), a physician, researcher, and the author of Should I Be Tested for Cancer? Maybe Not and Here’s Why, encourages people to approach cancer screening with a full understanding of both its advantages and its risks. In the book, he explores the issues raised by screening and early detection, including the  risks of overdiagnosis and overtreatment, and presents a detailed picture of what cancer screening tests can and cannot do. In order to help improve the communication and understanding of health data, Welch and his colleagues Steven Woloshin and Lisa M. Schwartz co-authored Know Your Chances: Understanding Health Statistics, which provides readers with the tools to interpret health statistics and better understand risk.