Finding usability problems through heuristic evaluation

Usability specialists were better than non-specialists at performing heuristic evaluation, and “double experts” with specific expertise in the kind of interface being evaluated performed even better. Major usability problems have a higher probability than minor problems of being found in a heuristic evaluation, but more minor problems are found in absolute numbers. Usability heuristics relating to exits and user errors were more difficult to apply than the rest, and additional measures should be taken to find problems relating to these heuristics. Usability problems that relate to missing interface elements that ought to be introduced were more difficult to find by heuristic evaluation in interfaces implemented as paper prototypes but were as easy as other problems to find in running systems.