What We Don’t Know Can Hurt Our Patients: Physician Innumeracy and Overuse of Screening Tests

Patients, the public, and even health professionals enthu-siastically support screening for disease, especially screen-ing for cancer. Unfortunately, whether many members of these groups fully understand the benefits and risks that would allow an informed decision is not clear. This has not, however, dampened the enthusiasm for screening. A decade ago, Schwartz and colleagues (1) found that 87 % of a national sample of adults believed that routine cancer screening is al-most always a good idea and 74 % said that early detection saves lives most or all of the time—to the point that more than one third considered an 80-year-old person who declined screening to be irresponsible. As chair of the U.S. Preventive Services Task Force when the draft recommendation on prostate-specific antigen (PSA) screening was released, I find my e-mail inbox replete with personal stories from men who are convinced that PSA screening saved their lives. However