In this article, we present results from a study of how varying e-mail “cover letters” in the implementation of an online survey can influence response rates. Historically, there is little evidence that the content of survey cover letters has a strong effect on response rates in off-line survey environments, although empirical research on this question is limited and some research has pointed to small, but significant, effects due to varying letter content. Online self-completion surveys differ from paper versions in that the link that survey targets must click on to complete the survey is embedded in the “cover letter” e-mail. As such, we have reason to suspect that the content of such e-mails may affect the likelihood that targets respond to the survey and influence the quality of the responses that they provide.
Fazekas, Z., Wall, M. T., & Krouwel, A. (2014). Is It What You Say, or How You Say It? An Experimental Analysis of the Effects of Invitation Wording for OnlinePanel Surveys. International Journal of Public Opinion Research, 26(2), 235–244. https://doi.org/10.1093/ijpor/edt022