According to a new survey, a majority of U.S. women remain unaware of overdiagnosis and overtreatment, two of the biggest risks associated with breast cancer screenings.

"Although it is difficult to pinpoint just how common cancer overdiagnosis is, there is growing expert consensus that the phenomenon is real and may require a re-evaluation of aggressive screening strategies," wrote lead author Rebekah Nagler, PhD, of University of Minnesota, Minneapolis, and colleagues.

The study, published in the October issue of Medical Care, reported that less than 20 percent of U.S. women know about overdiagnosis, overtreatment and their potential risks.

Overdiagnosis generally refers to detection of cancer that is slow to develop and would not have caused health issues over a woman’s lifetime, while overtreatment refers to unnecessary care that can include surgery and medications that expose women to side effects with minimal health benefits.

The study was used as a method to assess women’s awareness of and reactions to statements about overdiagnosis and overtreatment. The study included 429 women between the ages of 35 to 55.

• 16.5 percent of women were aware of potential overdiagnosis from breast cancer screening.
• 18 percent of women knew of the potential risk of overtreatment.
• Women under 40 were the least likely to have heard about overdiagnosis.
• Most women did not find statements about overdiagnosis or overtreatment believable or persuasive.
• Women who had a recent mammogram were unconvinced by the overdiagnosis and overtreatment arguments.

The results were consistent with prior research and survey studies in the U.S., Australia and the U.K.

Because many U.S. women view mammogram screenings favorably, the authors noted the challenge may be in providers communicating with patients about associated risks.

“Communication interventions, supported by evidence from health communication research, are necessary to improve patient understanding of screening’s harms, promote informed decision making, and, in turn, ensure high-value care,” Nagler and colleagues wrote.