In web- or online survey, the participants get pre-recruited first. They derivate from a representative random telephone sample, an access panel or from any other offline recruitment. The structures of "online-population" or specific target groups can be displayed correctly by quotation. Depending on the study concept, different quality and safety measures will be applied to achieve valid results.

In on-site survey every umpteenth visitor of a website will be adressed by the "intercept method" or will be asked for participation. By this means meaningful results can be achieved according to design, usability and to the content of websites.

The appllied survey system (voxco) seamlessly combines online and CATI. Thereby, i.e. already running representative interviews can be finished by the interview partner if this is wanted and determined in the survey design.

A particular form of the mix-mode survey is the co-browsing method where respondents become intergrated online into the CATI interview in realtime.

But also personal interviews in the teststudio (CAPI) can be combined with the online system to take advantage of personal interviews and online-aided quota control, real-time reporting etc. in studio.web