The Effectiveness of Mailed Invitations for Web Surveys and the Representativeness of Mixed-Mode versus Internet-only Samples

Wolfgang Bandilla, Mick P. Couper, Lars Kaczmirek

Abstract


E-mail is a common invitation mode for Web surveys. However, collecting e-mail addresses in another mode may raise privacy concerns among respondents. In our previous study, fewer than half the respondents provided an e-mail address. In this paper we report on an experiment to test the efficacy of asking for e-mail addresses. Respondents to the 2012 German General Social Survey (ALLBUS) who reported having Internet access at home were randomized to two groups, with one group not being asked for their e-mail address, while the other being asked. Using a mailed invitation to a follow-up Web survey, we explore the effect of this request on the subsequent response rate. We also followed up all cases (including those who reported not having Internet access at home) with a mail survey to explore the effect of adding mail in a sequential mixed-mode design. We find that asking for e-mail address does not appear to have negative effects on subsequent response. We also find that a mixed-mode design substantially increases response rates and brings the follow-up sample more in line with the ALLBUS in terms of selected demographic and attitudinal variables.

Keywords


Web survey; mixed-mode; invitation mode

Full Text: HTML PDF

About Survey Practice Our Global Partners Disclaimer
The Survey Practice content may not be distributed, used, adapted, reproduced, translated or copied for any commercial purpose in any form without prior permission of the publisher. Any use of this e-journal in whole or in part, must include the customary bibliographic citation and its URL.