New technologies beget new science

Image cour­tesy of B. Goncalves, et al./Indiana University

Since you’re reading this blog, you’ve prob­ably heard of net­work sci­ence and big data by now. It’s the field of research in which sci­en­tists leverage the amazing amounts of data we have these days to under­stand the world’s myriad net­works, be they social, genetic or even transportation-​​based (ie., the net­work of air­line flights across the globe). Under­standing them can lead to a variety of out­comes, from pre­venting the spread of an epi­demic through the pop­u­la­tion to pre­dicting the next Amer­ican Idol.

Through this work, an entirely new field is emerging and a dif­ferent breed of researcher will have to grow up with it, said pro­fessor Alessandro Vespig­nani. “There’s no way back. When you invent the micro­scope, then you have to use it, even if the optics aren’t per­fect yet.”

Last month, Vespig­nani and a group of researchers from Penn State, Har­vard and other insti­tu­tions around the globe pub­lished a review paper in the journal PLOS Com­pu­ta­tional Biology called Dig­ital Epi­demi­ology.

This is the name they’ve given to the emerging field, which has been devel­oping over the last five years as a result of the data influx coming from new media and dig­ital elec­tronic devices.

The web is so per­va­sive in the lives of every­body today. It’s not any­more a new tech­nology,” said Vespig­nani. “What is new is the sci­ence we can do through it.” That “future breed” of researchers, say the authors, will need to be familiar not only with advanced com­pu­ta­tional tech­niques and ana­lyt­ical processes, but also with clas­sical epidemiology.

The idea for the paper, which also includes NIH pro­gram man­ager Patricia Mabry in the authors list, came about after the Data Sci­ence & Epi­demi­ology work­shop, orga­nized by first author Marcel Salathe, last October. The work­shop was held at Penn State’s Center for Infec­tious Dis­ease Dynamics.

This was one of the moments in which we dis­cussed where we are in the field and what we can do more of,” said Vespig­nani. “There’s a wave of activity. And one way or another, these new capac­i­ties, tech­nolo­gies and approaches are going to really make a rev­o­lu­tion in the end.”

The field of epi­demi­ology is well estab­lished and uses tech­niques that are in many cases 100 years old. And while we cannot throw out those methods entirely, the “gold mine of data” on which we now sit requires the explo­ration of new, pre­vi­ously unask­able ques­tions. In clas­sical studies, 500 or 1000 sub­jects make for a sub­stan­tial cohort. When sci­en­tists probe online chat rooms, Twitter feeds and cell phone data, they can access pop­u­la­tions of mil­lions of people. What these data lack in con­trol­la­bility and “clean­li­ness,” they make up for with the power of size, said Vespignani.

But what does it all look like, exactly? How can you do an epi­demi­o­log­ical study without going door-​​to-​​door to ask people things like whether or not they will get their flu vac­ci­na­tion this year or how many cig­a­rettes they smoke? Vespig­nani and the other authors envi­sion large-​​scale, web-​​based epi­demi­o­log­ical studies in which vol­un­teers field ques­tions about things like obe­sity and cig­a­rette smoking to col­lect data about peo­ples’ per­cep­tions and behav­iors. Co-​​author John Brown­stein, an asso­ciate pro­fessor at Har­vard Med­ical School and director of the Com­pu­ta­tional Epi­demi­ology Group at Children’s Hos­pital in Boston, has a project called “Flu Near You,” which tracks the flu virus by asking par­tic­i­pants to answer a short online survey once a week.

When they track the spread of infec­tious dis­eases across the globe, Vespignani’s group uses the net­works of air­line flights and cell tower activity to map out human mobility pat­terns. When you use the social net­work to track things like the spread of health knowl­edge, you’re just looking at a dif­ferent kind of map, Vespig­nani explained. “The model might use the same metaphor,” he said, “but it’s in a dif­ferent space – a social space, instead of a geo­graph­ical one.”

The emerging field of dig­ital epi­demi­ology may not be per­fect yet, it still needs some fine-​​tuning, but in the end, Vespig­nani and his col­leagues believe that it is the future epidemiology.