Applications and Recruitment Performance of Web-Based Respondent-Driven Sampling: Scoping Review

Abstract

Background Web-based respondent-driven sampling is a novel sampling method for the recruitment of participants for generating population estimates, studying social network characteristics, and delivering health interventions. However, the application, barriers and facilitators, and recruitment performance of web-based respondent-driven sampling have not yet been systematically investigated. Objective Our objectives were to provide an overview of published research using web-based respondent-driven sampling and to investigate factors related to the recruitment performance of web-based respondent-driven sampling. Methods We conducted a scoping review on web-based respondent-driven sampling studies published between 2000 and 2019. We used the process evaluation of complex interventions framework to gain insights into how web-based respondent-driven sampling was implemented, what mechanisms of impact drove recruitment, what the role of context was in the study, and how these components together influenced the recruitment performance of web-based respondent-driven sampling. Results We included 18 studies from 8 countries (high- and low-middle income countries), in which web-based respondent-driven sampling was used for making population estimates (n=12), studying social network characteristics (n=3), and delivering health-related interventions (n=3). Studies used web-based respondent-driven sampling to recruit between 19 and 3448 participants from a variety of target populations. Studies differed greatly in the number of seeds recruited, the proportion of successfully recruiting participants, the number of recruitment waves, the type of incentives offered to participants, and the duration of data collection. Studies that recruited relatively more seeds, through online platforms, and with less rigorous selection procedures reported relatively low percentages of successfully recruiting seeds. Studies that did not offer at least one guaranteed material incentive reported relatively fewer waves and lower percentages of successfully recruiting participants. The time of data collection was shortest in studies with university students. Conclusions Web-based respondent-driven sampling can be successfully applied to recruit individuals for making population estimates, studying social network characteristics, and delivering health interventions. In general, seed and peer recruitment may be enhanced by rigorously selecting and motivating seeds, offering at least one guaranteed material incentive, and facilitating adequate recruitment options regarding the target population’s online connectedness and communication behavior. Potential trade-offs should be taken into account when implementing web-based respondent-driven sampling, such as having less opportunities to implement rigorous seed selection procedures when recruiting many seeds, as well as issues around online rather than physical participati...

Improving web-based respondent-driven sampling performance among men who have sex with men in the Netherlands

“…An option to motivate participants to take art in a study could be to increase the amount of the participation incentive. A review of WebRDS surveys found that studies that did not offer at least one guaranteed material incentive reached lower percentages of successfully recruiting participants and fewer waves, indicating that the amount of participation reward or another incentive is a big motivator for participants [ 16 ]. However, our results show that getting a high reward is actually the least important factor for forwarding an invitation.…”

“…Higher monetary rewards have proven to be successful to create a sufficiently large sample in a study carried out in the United States [ 15 ], but this is very expensive and not feasible for many studies. High monetary rewards are also considered unethical and may lead to cheating behavior [ 16 ]. Another option to prevent recruitment chains from going extinct is to allow higher numbers of recruits per individual.…”

“…Web-based RDS (WebRDS), an online variation of RDS, where recruitment is performed with digital tools, could possibly overcome some of the disadvantages of traditional RDS [ 16 , 18 ]. Internet-based methods are easily accessible for participants in high income countries and are therefore an efficient possibility for researchers.…”

“…Nevertheless, WebRDS has the potential to produce sufficiently large samples of MSM in high-income countries [ 17 ]. In a review on studies using WebRDS, Helms et al found that sample sizes were between 19 and 3448 with recruitment chains of up to 29 waves [ 16 ].…”

Evaluation of a Web-Based Culturally Sensitive Educational Video to Facilitate Informed Cervical Cancer Screening Decisions Among Turkish- and Moroccan-Dutch Women Aged 30 to 60 Years: Randomized Intervention Study

“…One major strength of this study was its design as a randomized intervention study. Worldwide, this study also had one of the largest samples successfully recruited using web-based RDS [ 31 ]. In addition, our CSEVs were systematically developed based on extensive qualitative and quantitative research among Turkish- and Moroccan-Dutch women [ 5 ].…”