Usability testing is the practice of sitting real users down in front of a website (or a prototype of a website) and trying to identify the problems they experience in trying to use it.
There are a number of issues to consider when commissioning a usability testing session, here are 2 of the most important:
The choice of users themselves
Testing sessions’ results are only as good as the subjects you select to test the site against. They should be broadly representative of your target audience, both in terms of traditional demographics (e.g. age, social class etc.) and Internet-literacy.
This last point of Internet literacy is especially important. Many sites try to cut corners by testing a site with friends or colleagues, but this misses the whole point of usability testing – it’s not about what you, or people like you – think, but rather about what the site’s actual target audience will think.
I’ve lost count of the number of web design agencies who proclaim to test their sites, but upon further questioning admit that all they really do is send a URL round the office and ask for comments – that is not proper testing!
People working in a web design agency, who go to work in trainers, drink café lattes and use the Internet for their profession could hardly be described as a representative sample of users for the majority of websites.
So, in conclusion – make sure you are testing with the right people, so the results will be relevant to your site!
Analysis of results
User testing will result in observed phenomena (such as ‘this user could not find the ‘checkout’), but it will not be able to explain those phenomena in isolation.
Results alone are not enough – you need to analyse them.
It is important for anybody thinking about testing their site with users to make sure that there are people with the right skills and expertise present to analyse the tests. The easiest way to find out if the agency/person you have chosen to conduct the tests is going to deliver real value is to ask about their experience and academic background.
Explaining why people do things (i.e. why couldn’t users find the checkout) requires an understanding of user-psychology – a strong background in human-computer interaction, psychology or cognitive science is always desirable.
The whole point of analysing a test is to understand why people are having problems, which will then allow any re-design to properly address these problems. Any re-design conducted without such analysis runs the risk of being a waste of time, effort and money, as you never really understood the problem in the first place and, therefore, might not have solved it.