You can, of course, pay usability professionals a small fortune. Or you can do it yourself... with incredibly useful results. And as we’re all in favour of achieving your aims as cost effectively as possible, we’re unsurprisingly keenest on the second option.
So with thanks to this helpful piece from usability.gov (http://usability.gov/methods/analyze_current/goals.html), here are 4 main headings that you can use to set your own usability criteria.
- Time – for example, the time it takes to get to a particular page or carry out a particular task (register, buy something, download a document) on the site. What are the key tasks that you want users to carry out on your site? Decide on an acceptable timescale for each and test it out – a good way of doing this is to visit other sites and see what you find acceptable there.
- Accuracy – best measured via lack of accuracy, such as errors, misunderstandings and unproductive actions. For example, you can measure the number of errors in using an application, the number of misunderstandings of information provided or the number of unproductive navigation choices. Decide on some key tasks, see how accurately users perform them and select your goals. As above, looking at other sites can help you decide what you think is an acceptable level of accuracy.
- Overall success – kind of obvious, this one, because if the user can’t do what they want to, there’s clearly a big problem. But you can break this down into the specifics of how people achieve their goals – for example, if they use the ‘Help’ button, how long they take to find what they need and return to the task. Or if they use ‘Search’, how long it takes them to find what they need. Once again, looking at other sites can help you establish what is acceptable.
- Satisfaction – both overall satisfaction and specific satisfaction regarding particular parts of your site (navigation, search, language etc). Best done using a scale – with 1 as ‘not at all satisfied’ and 10 as ‘completely satisfied’.
Finally, remember this one? An excellent downloadable guide which includes advice about how to conduct your own usability studies. Have a read of: http://www.publiczone.co.uk/whats-happening/user-research-handbook/ We’ve recommended it before but it’s worth mentioning again, because it’s full of great, free of charge advice.