First Steps

Burning questions
(continued)

The study doesn't track lung metastasis, so Murin will be looking at five- and 10-year survivability statistics between current and former smokers and nonsmokers diagnosed with breast cancer.

"The Nurses' Health Study is a good database to use because it takes into account other lifestyle factors," Murin explains. "When you make a connection between smoking and a disease, you have to ask, is it because of smoking or other factors? Is it because smokers don't eat right or don't exercise as much as nonsmokers? Is it because smokers' cancer is diagnosed at a later stage?"

The nurses' health study database "helps us tease out the impact of smoking from other behavioral factors," she says.

That's part of the role of epidemiologists like Murin. They clarify relationships by connecting the dots of millions of pieces of data into understandable hypotheses. And in the end, their conclusions help all of us better understand the risks we take.