Social media, public health and behavior change: Quality vs. quantity in online networks

New research from the Massachusetts Institute of Technology is adding to our understanding of how to apply online social networks to public health behavior change. Damon Centola, from MIT's Sloan School of Management created a social network of 1528 people to investigate which of two models of social networks would be more likely to promote a health-related behavior: "Long ties" (distant connections with many others) or dense cluster connections (closer contacts with folks you know better.) The public health behavior he was seeking to encourage was to get participants to sign up for an online health information forum.

His results, while somewhat intuitive, provide fodder for consideration among public health planners. Among participants enjoying the closer social connectivity of clusters, 54% registered for the health service, compared with 38% of folks with more distant "long ties."  Clusters inspired adoption four times faster. And once folks joined the health resource forum, the number of friends also signed up influenced their likelihood of returning. While only 15% of participants with a single friend in the forum returned to it after registering, more than 30% of those with two friends returned, and over 40% of those with three or more friends in the forum returned.

"Social reinforcement from multiple health buddies made participants much more willing to adopt the behavior, Centola writes in his paper, published in the September 3rd issue of Science.

Or in other terms:  A simple contagion, such as a spreading disease, can spread with only a single contact. But more complex contagions, such as health behavior change or disease preventive activities, need repeated reinforcement from multiple social contacts.

Previous public health research has delved into the social contagiousness of health conditions such as obesity, essentially that many of the external conditions and individual behaviors that are the root for health and disease are learned or shared from our closest contacts. Check out this amazing animation from Nicholas Christakis, tracking the social contagiousness of obesity over several decades in the Framingham Heart Study. This new research helps flesh out the role that social media and online networks may play in magnifying or inhibiting underlying social and behavioral determinants of health.