The touching stories that advocacy groups are so good at telling—the 49-year old mother whose breast cancer was detected by an early mammogram before it had spread; the 60-year-old neighbor who had a prostate tumor removed thanks to a routine PSA test—should inspire scientists to use anecdotes of their own, argue two doctors from the University of Pennsylvania.

In the scientific realm, anecdotal evidence—the individual patient, the single result—tends to be shunned in favor of large, dense data sets and impersonal statistical analyses. Although that foundation must remain the core of solid research, examples and narratives should be invoked to round out the explanation of what the hard science says, Zachary Meisel and Jason Karlawish, both of the Perelman School of Medicine at Penn, contended in an essay published online Tuesday in JAMA, Journal of the American Medical Association. "Stories are an essential part of how individuals understand and use evidence," they wrote. And they can have a powerful effect on public opinion and policy.

"Each time, those who espouse only evidence—without narratives about real people—struggle to control the debate. Typically, they lose," Meisel and Karlawish observed. In the wake of recommendations for reduced breast and prostate cancer screenings from the U.S. Preventive Services Task Force, many cancer survivors and cancer advocacy groups jumped in to tell the stories of how early screening had saved lives.

Many scientists point out that these stories and stats can be misleading because overall survival also increases when more non-life-threatening cancers are detected—and misses the many potential downsides to untargeted screening. That's where scientists can step up with stories of their own, such as that of the young woman who underwent a series of invasive and stressful biopsies only to reveal that a mass in her breast was not malignant—or the example of the middle aged man who was rendered incontinent after surgery to remove a prostate growth that was not likely to have killed him. Compelling stories could also help counter unwarranted fears about childhood vaccines, by telling the tale of one of the many unvaccinated children who got measles because parents were worried about the purported link to autism.

Relatable, first person narratives could also make the scientific process much clearer and more accessible. If, before releasing the publicly controversial—but evidence-supported—2009 guidelines on mammography, the U.S. Preventive Services Task Force had explained their own process and personal deliberations, it might have built "a substantially more compelling perspective" rather than prompted "a confused and angry public" response with dehumanizing statistics, Meisel and Karlawish asserted.

And the dry old scientific data supports this notion. "Narratives, when compared with reporting statistical evidence alone, can have uniquely persuasive effects in overcoming preconceived beliefs and cognitive biases," the researchers noted.