Social Networks and Hidden Populations
Last semester I took a sociology class at Cornell entitled “Drugs and Society,” taught by Professor Douglas Heckathorn. In the class, we learned about injection drug users, and the difficulties associated with sampling hidden populations such as the injection community. Hidden populations are those that have unknown size and boundaries, and in which there are privacy concerns for individual members. We were then introduced to Respondent-Driven Sampling, or RDS, a method Professor Heckathorn himself developed. RDS uses members of the hidden population, called seeds, to recruit their peers into the sample, using their own personal social networks. The rationale behind the use of RDS is that no one can know or access the dynamics of a hidden population better than the individual members of that population.
In the attached paper entitled “AIDS and Social Networks,” Heckathorn and his co-authors describe how RDS, when used as the recruitment mechanism for Peer-Driven Intervention, is more effective in preventing the transmission of HIV within the IDU population when compared to the standard form of street-based outreach prevention. Peer-Driven Intervention, a network-based HIV prevention intervention, uses members of the IDU population to recruit and inform other members using their social networks, as well as a dual-incentive system. Studying the network structure of the IDU community is therefore important in two ways. Social ties “serve as the conduit through which infection is transmitted,” but the same ties can then be used to disseminate information on HIV prevention. Peer-Driven Intervention demonstrates that social networks can be harnessed on behalf of HIV prevention efforts, and that the same set of social ties within a network can play multiple roles. As the paper notes, it is ironic that it is in the most extensive networks in which HIV spreads rapidly that HIV prevention techniques are the most effective.
http://www.respondentdrivensampling.org/reports/sociological_focus.pdf