Usability Testing
http://www.usability.gov/pdfs/chapter18.pdf

Usability.gov
2006

Abstract:

There are two major considerations when conducting usability testing. The first is to ensure that the best possible method for testing is used. Generally, the best method is to conduct a test where representative participants interact with representative scenarios. The tester collects data on the participant's success, speed of performance, and satisfaction. The findings, including both quantitative data and qualitative observations information, are provided to designers in a test report. Using 'inspection evaluations,' in place of well-controlled usability tests, must be done with caution. Inspection methods, such as heuristic evaluations or expert reviews, tend to generate large numbers of potential usability 'problems' that never turn out to be actual usability problems.