A recent article in Journal of Official Statistics offers a useful way for us to think about the respondent decision making process. The authors, some of whom are involved in websm.org, describe four stages in the participation process: (1) initial contact by e-mail or snail mail; (2) initial accessing of the questionnaire by login or clickthrough; (3) starting the survey by clicking to the first question; and (4) completing the full survey. The authors’ goal is to describe a survival model that depicts how the original sample winnows itself down to the hopefully-not-too-small proportion of sample members who eventually complete.
What I find interesting is the simple setting out of the process with the obvious implication that we should look closely at each stage and do our best to optimize it so that we get as high a response rate as we can manage. The stage at which we/MSI almost always lose the greatest number of people? Stage 1. Once we get them to the site we do pretty well, but convincing respondents to participate is a complex difficult task. More on that another time.
You can find the article online here: http://www.jos.nu/Articles/abstract.asp?article=203451.