Addressing Public Health Needs by Promoting Prosocial Behaviors Through Social Media

Online social networks have the potential to encourage behaviors that improve the health and well-being of society at an unprecedented scale. We examine the impact of Facebook’s blood donation tool on voluntary blood donation in three large countries. Quasi-experimental evidence in the United States indicates that the tool caused an increase in blood donation among all donors (+4.0% [95% CI: .04% to 8.0%]), and particularly among new blood donors (+18.9% [95% CI: 4.7% to 33.1%]) during the tool’s three-month staggered rollout. Longitudinal evidence from Brazil and India indicates that the share of donors who both received a message from the tool and stated they were influenced by Facebook to donate blood increased from 0% to 14.1% [95% CI: 12.1% to 16.2%] in the first year. These findings demonstrate that social networks can support public health by encouraging offline prosocial behavior at scale