River Sampling

Also known as: River Sample, Intercept Sampling, Real-Time Sampling

Recruitment technique where participants are invited to surveys in real time as they browse associated websites.

River Sampling is a respondent recruitment technique where participants don't belong to a pre-registered panel, but are intercepted and invited to participate in real time while browsing websites, apps, or platforms associated with the research company.

Its main advantage over traditional online panels is that it reduces 'professional respondent bias': participants are not people actively seeking surveys, but occasional users who encounter the invitation while doing something else.

Its main limitation is the lower ability to find specific or niche profiles (e.g., regular buyers of a specific brand), where the targeted online panel is more efficient.

River sampling is frequently combined with online panels to complement samples and increase data source diversity.