What We Don't Know Can Hurt Our Patients: Physician Innumeracy and Overuse of Screening Tests
- Virginia A. Moyer, MD, MPH
+ Author Affiliations
- From Baylor College of Medicine, Houston, TX 77030.
Patients, the public, and even health professionals enthusiastically support screening for disease, especially screening 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 almost 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, even for mammography screening for breast cancer, which is more effective than even the most optimistic estimates for PSA screening, several analyses have demonstrated that the vast majority of women with screen-detected breast cancer have not had their lives saved by screening, but rather have been diagnosed early with no change in outcome or have been overdiagnosed (2, 3). In a survey about the decision-making process for cancer screening, most respondents could not correctly answer a single open-ended knowledge question about any of the 3 types of cancer covered in the survey, even though respondents …