Response rates were compared across a postal and a Web-based survey containing the same questions about preferences for future for the design of future nursing homes which were sent to a random sample of 10,000 individuals aged 50-75 years. The 10,000 individuals were randomly allocated to receive a postal questionnaire or a letter with a Web link to an online version of the same questionnaire. The Web-based survey gave a significantly lower response rate than the postal survey. The Web-based version improved the sample representativeness with respect to gender but worsened the representativeness with respect to age. Respondents' characteristics in the Web-based survey differed significantly from those of respondents in the postal survey with respect to income, education, civil status and health status. The Web-based version improved data quality by significantly lowering the number of item non-response and 'don't know' answers. Respondents found it easier to answer the Web-based survey. The cost per response was significantly higher for the Web-based survey because of the significantly lower response rate compared to the postal survey.
Mickael Bech, University of Southern Denmark
Institute of Public Health
Morten Bo Kristensen, University of Southern Denmark
Centre for Applied Health Services Research and Technology Assessment