Strömdahl Susanne, Lu Xin, Bengtsson Linus, Liljeros Fredrik, Thorson Anna
Department of Public Health Sciences, Karolinska Institutet, Stockholm, Sweden.
Department of Public Health Sciences, Karolinska Institutet, Stockholm, Sweden; College of Information System and Management, National University of Defense Technology, Changsha, China.
PLoS One. 2015 Oct 1;10(10):e0138599. doi: 10.1371/journal.pone.0138599. eCollection 2015.
Respondent driven sampling (RDS) was designed to study 'hidden' populations, for which there are no available sampling frame. RDS has been shown to recruit far into social networks of the study population and achieve unbiased estimates when certain assumptions are fulfilled. Web-based respondent driven sampling (WebRDS) has been implemented among MSM in Vietnam and produced a sufficient sample of MSM. In order to see if WebRDS could work in a 'hidden' population in a high-income setting, we performed a WebRDS among MSM in Sweden to study a sensitive topic, sexual risk behaviour for HIV/STI and Internet use.
A cross-sectional survey was implemented between July 11, 2012 and January 21, 2013 by using a WebRDS software. Men, fifteen years old or above, who reported having ever had sex with another man were included. The web-survey explored sociodemographics, sexual risk behaviour for HIV/STI and Internet use.
The WebRDS process created a sample of 123 eligible respondents. The mean age among participants was 32 years old. All respondents reported having had unprotected anal intercourse (UAI) with at least one regular and one casual sex partner during the last 12 months. On average participants reported having had UAI with three casual sexual partners and in total having had seven casual sex partners during the last 12 months.
The WebRDS produced a sample of Internet-using MSM in Sweden who all reported sexual risk behaviour for HIV/STI during the last 12 months. It holds promise for future online studies among MSM and a possibility to reach MSM at risk for HIV/STI with interventions or information. Some challenges were found including short recruitment chains, and further research need to address how to optimize WebRDS online recruitment methods in high income settings.
应答驱动抽样（RDS）旨在研究没有可用抽样框架的“隐藏”人群。当满足某些假设时，RDS已被证明能够深入研究人群的社交网络并实现无偏估计。基于网络的应答驱动抽样（WebRDS）已在越南的男男性行为者（MSM）中实施，并产生了足够数量的MSM样本。为了探究WebRDS是否能在高收入环境下的“隐藏”人群中发挥作用，我们在瑞典的MSM中开展了一项WebRDS，以研究一个敏感话题，即艾滋病毒/性传播感染的性风险行为和互联网使用情况。
在2012年7月11日至2013年1月21日期间，使用WebRDS软件进行了一项横断面调查。纳入了15岁及以上且报告曾与另一名男性发生过性行为的男性。网络调查探究了社会人口统计学特征、艾滋病毒/性传播感染的性风险行为和互联网使用情况。
WebRDS过程产生了123名符合条件的应答者样本。参与者的平均年龄为32岁。所有应答者均报告在过去12个月内与至少一名固定性伴侣和一名临时性伴侣发生过无保护肛交（UAI）。参与者平均报告在过去12个月内与三名临时性伴侣发生过UAI，总共拥有七名临时性伴侣。
WebRDS在瑞典产生了一个使用互联网的MSM样本，他们均报告在过去12个月内有艾滋病毒/性传播感染的性风险行为。它为未来在MSM中开展在线研究带来了希望，并且有可能通过干预措施或信息接触到有艾滋病毒/性传播感染风险的MSM。研究发现了一些挑战，包括招募链较短，进一步的研究需要解决如何在高收入环境中优化WebRDS在线招募方法的问题。
