Once upon a time, women were encouraged to get mammograms to prevent breast cancer — and that was essentially that. Today, debate swirls over the potential for breast cancer screening to lead to overdiagnosis and overtreatment. Even as the percentage of women who undergo mammograms falls short of public health goals, and breast cancer kills approximately 40,000 women annually, health professionals continue to spar about guidelines advising when and how often women should get screened. Now, amid the combustive, and sometimes confusing, back and forth, experts have begun debating another common practice: when health plans offer women financial incentives to get mammograms.

“Offering the incentives suggests: Do this thing — get screened — because it’s good for you, and we’ll give you something else that’s nice, because we think you’re doing the right thing,” says Harald Schmidt, an assistant professor of medical ethics and health policy at Perelman School of Medicine at the University of Pennsylvania in Philadelphia. But, he adds, the reality is more nuanced.

In a perspective piece published last month in the Journal of the American Medical Association, Schmidt called financial incentives for mammography — such as those he found in an online search, which ranged from $10 to more than $200 being offered by insurers and self-insured companies — “an ethically disconcerting distraction in a complex decision-making process.” Instead of offering dollars — or T-shirts or mugs or movie tickets — in exchange for undergoing breast cancer screening, he argues that incentives should be doled out to women for reviewing information on the potential benefits and harms associated with breast cancer screening. That way they could make their own “evidence-based, active choice,” he says, whether that leads to undergoing a mammogram or holding off on getting screened.

But others say incentives are just what’s needed to encourage women to undergo the widely supported practice of routine mammograms — even if guidelines differ on when women should first be screened and how often they should have a mammogram.

“Incentives can be very useful for getting people to do things that they might otherwise not get around to doing,” says Robert Smith, vice president of cancer screening for the American Cancer Society. “We find it’s a challenge to get people to engage in preventive care, and it’s not just breast cancer screening; it’s colorectal cancer screening, cervical cancer screening — it’s all of these.” Noting the examples Schmidt highlighted of financial incentives designed to encourage women to undergo mammograms, he added: “Sometimes, these little incentives — and some of them were actually pretty substantial, I was impressed — can make a difference.”

Health incentives are becoming increasingly common to influence individual behavior, such as rewards offered by employers and health plans to employees who quit smoking. But Schmidt contends what makes breast cancer screening different is that patients face not only the potential for benefit — in some cases, lifesaving cancer treatment — but harm, ranging from worry over false positive tests to unnecessary treatment. And, he argues that incentives distract from that. “Given that you have to do very, very complex assessments of benefits and harms, it just gets in the way; it isn’t needed and it presumes that screening will be good for everyone,” he says.

What’s more, Schmidt notes that these health plans routinely offer financial carrots to women who undergo annual mammograms starting at age 40, despite the fact that there’s strong disagreement over whether women should undergo screening beginning at age 40, or a decade later, at 50, and to do so every year or every other thereafter.

But despite the debate, Smith emphasizes that current guidelines broadly endorse routine breast cancer screening and, as such, he disagrees with Schmidt’s characterization of mammogram incentives being “ethically concerning.” Smith says he would feel differently about incentives offered to undergo prostate cancer screening, since the ACS doesn’t make a direct recommendation on whether men should get screened. “We recommend that men make an informed decision about prostate cancer screening with their doctor, where they would have an opportunity to explore their own values and their preferences, and the implications of what happens if you get tested — and what might happen if you don’t.”

Regarding breast cancer screening incentives, Smith is quick to add, however, that incentive requirements should match the guidelines set by major health organizations, such as ACS. Schmidt noted at least one plan offering women money for undergoing mammograms as early as 35, which isn’t supported by the ACS or other organizations making recommendations on breast cancer screening. “We recommend annual screening beginning at age 40 and we recommend that women continue screening as long as they’re in good health,” Smith says. By comparison, the U.S. Preventive Services Task Force, an independent group of experts that makes recommendations on preventive care, advises that women first be screened at age 50, and continue getting mammograms every other year through age 74.

New York Life, whose health insurance carrier is Aetna, offers its female employees who are 40 and older a $250 credit to undergo a routine annual mammogram, a timeline that’s in step with guidelines from the ACS, American College of Radiology and the American College of Obstetricians and Gynecologists. The money, for example, can be applied to their deductible. “New York Life offers incentives to encourage its employees to engage in healthy behaviors,” says company spokeswoman Terri Wolcott.

“Health plans have consistently prioritized preventive screenings for patients, in particular because these preventive steps are core to plans’ disease-management and care-coordination programs that identify risk factors early and address them directly,” says Clare Krusing, spokeswoman for industry group America’s Health Insurance Plans. “Plans routinely connect with patients and providers to make sure women are receiving timely screenings, including mammograms.”

Schmidt notes that a simple Google search yields numerous major insurers and large companies that offer financial incentives to policyholders for undergoing mammograms. But what many see as a simple incentive designed to prompt women to undergo recommended cancer testing, others see as obscuring a more complex reality.

For a long time, the societal view of mammography has been that it’s “basically a harmless thing that you want to do just to be safe,” says Dr. Kenny Lin, associate professor of family medicine at Georgetown University in the District of Columbia, who was previously a medical officer for the U.S. Preventive Services Task Force program at the Agency for Healthcare Research and Quality. “But in the past few years I think there’s [been] increasing recognition that this is definitely a double-edged sword.” Depending on the patient, a mammogram could possibly lead to more harm than good, he notes, from idle worry over a false positive to unnecessary surgery.

The most controversial age group is 40 to 49, Lin says. That’s the group for which the USPSTF says evidence is insufficient to recommend routine breast cancer screening, and instead, says it’s an individual decision, t aking into account a patient’s values regarding specific benefits and harms. In this age group, he points to estimates the USPSTF used to make it’s recommendations: that fewer than 1 in 1,000 women would be saved over the next 10 years by undergoing annual mammograms. Put another way, those estimates suggest that without screening, 7 in about every 2,000 women in their 40s will die of breast cancer in the next 10 years, compared with 6 in 2,000 if women are screened.