Reaching hard-to-survey populations: Mode choice and mode preference

This study assesses the effect of response-mode choices on response rates, and responsemode preferences of hard-to-survey populations: young adults, full-time workers, big city inhabitants, and non-Western immigrants. Using address-based sampling, a stratified sample of 3,496 households was selected. The first group of sample members was contacted face to face and could choose between a CAPI and web response mode. The second group, contacted by telephone, could choose between CATI and web. The third group, contacted by telephone, was randomly allocated to a response mode. Our address-based sampling technique was successful in reaching most of the hard-to-survey groups. Insufficient numbers of non- Western immigrants were reached; therefore this group was excluded from our analyses. In our mixed-effect models, no significant effects on the willingness to participate were found for mode choice. We found that full-time workers and young adults were significantly more likely to choose web over CAPI when contacted face to face.