I recently read the results of some user testing we’d done on our website (part of a regular program of usability testing) and was shocked to realise that there were only 4 participants. That’s 4 out of the hundreds of thousands of users we have, and on the basis of their comments we are going to refine our website. Now whilst I agree with the principle of user testing I just don’t think that 4 is anywhere near enough to get a represeantative view of how the website works. It’s nowhere near a mathematically representative sample of our users and makes me wonder if it’s worth doing at all. I do realise that the more people you involve the more expensive it is and the longer it takes etc, but surely if you’re going to do it at all you want to make sure it’s worthwhile doing and will give you meaningful results?