When a medical test comes back positive for some terrifying disease, we want certainty: a clear diagnosis and a cure. This isn't always easy, according to doctor and medical researcher Steven Hatch. "A diagnosis is, much more often than not, a conjecture, and a prognosis is typically less certain than that." To navigate the hazy modern world of health and medicine, he says, doctors and patients must learn how to ask the right questions.
Snowball in a Blizzard is Hatch's first book, but the clarity and wit of his discussions rank with that of the best science writers. He explains the often counterintuitive world of medical research, the nature of uncertainty in diagnosis and treatment, and the role media plays in shaping our attitudes about medicine. His central idea is a "spectrum of certainty" that can be used to evaluate medical decisions. Hatch looks at the controversies around mammograms, PSA screening, Lyme disease and high blood pressure guidelines. He shows how confirmation bias and the human tendency to see nonexistent patterns can mar the judgment of even the best medical professionals, and how routine annual screenings can result in thousands of false positives every year for patients who then undergo unnecessary, expensive and potentially harmful treatments in the belief that they are being saved from diseases they never had. Hatch recommends that doctors cultivate humility, and that patients ask many polite educated questions. "Your medical plan is yours: you own it, and your doctor should be your guide, not your director." --Sara Catterall