In an earlier post (http://regbaker.typepad.com/regs_blog/2006/04/web_users_read_.html)I commented on some research by Jakob Neilsen showing that Web users tend to read the screen in a rough F-shaped pattern. Shortly thereafter we got some pushback from a client about our standard of the Next button on the left and the Previous button on the right. This client was not convinced by our white paper reporting on research that showed (1) a slight tendency to go back to a previous screen by mistake when the Previous button is on the left and (2) regardless of navigation button placement respondents seem to figure it out quickly.
Thinking about how best to respond to the client it occurred to me that the Neilsen research is still further support for a left side design. Since the last thing we want is to force respondents to go searching for stuff on a questionnaire screen, placing the key navigation button on the left side seems like a good idea. Now I've just seen another eye tracking study (Agnieszka Bojko, "Using Eye Tracking to Compare Web Page Designs: A Case Study," Journal of Usability Studies, vol 1, May 2006, pp. 112-120) that shows a similar focus by Web users on the left side of the screen. More and more one realizes that there is an informal standard among Web site designers to put the important stuff on the left side and as a result that's where Web users instinctively look. (Of course, there also is the Western standard of reading left to right.) Since our goal in Web survey design is always to make the survey task as easy and intuitive as possible, we should be sure we follow mainstream Web design principles, and those principles would seem to drive us to put the important stuff on the left side of the screen.