Improved methods for studying hard-to-reach populations published in PNAS
Respondent-driven sampling is a popular network-based approach to
sample hard-to-reach populations, where participants refer contacts
into the sample through a coupon system. It has been particularly
useful in HIV research where individuals most at risk (e.g., people
who inject drugs) are unlikely to participate in conventional sampling
schemes. Many major health organizations, including the Centers for
Disease Control and the World Health Organization, employ this
approach to quantify the prevalence of HIV in these at-risk groups.
Unfortunately this type of network sampling suffers from a significant
drawback: because referred contacts often share similar
characteristics, samples are highly correlated which can lead to
exceedingly variable estimates.
In work that just appeared in the Proceedings of the National Academy
of Sciences, IFDS members Sebastien Roch and Karl Rohe introduced a
new estimation technique for respondent-driven sampling with a
substantially reduced variability…