Estimating the Size of Hidden Populations Using Respondent-driven Sampling Data

Abstract

Background Respondent-driven sampling is used worldwide to estimate the population prevalence of characteristics such as HIV/AIDS and associated risk factors in hard-to-reach populations. Estimating the total size of these populations is of great interest to national and international organizations, however reliable measures of population size often do not exist. Methods Successive Sampling-Population Size Estimation (SS-PSE) along with network size imputation allows population size estimates to be made without relying on separate studies or additional data (as in network scale-up, multiplier and capture-recapture methods), which may be biased. Results Ten population size estimates were calculated for people who inject drugs, female sex workers, men who have sex with other men, and migrants from sub-Sahara Africa in six different cities in Morocco. SS-PSE estimates fell within or very close to the likely values provided by experts and the estimates from previous studies using other methods. Conclusions SS-PSE is an effective method for estimating the size of hard-to-reach populations that leverages important information within respondent-driven sampling studies. The addition of a network size imputation method helps to smooth network sizes allowing for more accurate results. However, caution should be used particularly when there is reason to believe that clustered subgroups may exist within the population of interest or when the sample size is small in relation to the population.

The prevalence and incidence of active syphilis in women in Morocco, 1995-2016: Model-based estimation and implications for STI surveillance

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Simple Linear Regression Model for Hidden/Hard-to-Reach/Elusive Populations

“…Johnston et al [20] followed. In order to address these shortcomings, Robertson et al [21] derived a uniformly minimum variance conditionally unbiased estimator for two-stage seamless phase II/III trials.…”

Using IBBS Survey Data and Stakeholder Consensus to Estimate Population Size of Female Sex Workers in Three South African Cities: Results and Recommendations From the 2013-14 South Africa Health Monitoring Survey (Preprint)

“…We used respondent-driven sampling (RDS) methods [9][10][11][12] that have been subsequently adapted for key populations HIV surveillance and population size estimation purposes [13][14][15][16][17][18][19]. We have described elsewhere how RDS recruitment operated in the SAHMS [2].…”