Online recruitment for an online survey study: Our experience of dealing with fraudsters

Online recruitment is cost efficient and can reach large sample size. It helps protect participants' privacy and confidentiality and is commonly used in research studies with sensitive topics and hard-to-reach target participants. However, widespread fraudulent responses along with missing data and multiple entries add complication to the data cleaning and analysis. This clinical-methods-brief described our experience of dealing with fraudsters in the recruitment process of an online study.

Based on our experience in an online cross-sectional survey study, we reported three methods used in the recruitment process, including website recruitment (https://www.chineseinla.com/), Facebook advertisement, and Facebook group recruitment.

The detected fraudulent rates were 11.11 %, 4.55 %, and 82.69 % for website recruitment, Facebook advertisement, and Facebook group recruitment, respectively. Strategies for us to identify the fake responses mainly included internet protocol checking, conflict answers to different survey questions, participant's name, and time stamp checking.

Fake data mixed in the research data threatens the validity and reliability of the study and may skew the research study results. A robust participant recruitment method and a data screening/cleaning protocol are necessary to ensure online studies' rigorous.