SUMI is a post-study questionnaire used to measure a product's general usability factor and five sub-factors. The sub-factors are efficiency (measure of how the software helps users complete their work), affect (general emotional reaction to the software), helpfulness (how much of the software is self explanatory and if there are documentation and help users can access), control (is the user in control of the product), and learnability (the speed in which users master the system and learn new features). The questionnaire involves a total of 75 items and requires a licensing fee. Each item is a statement (mixture of positive and negative) that can be answered by a three step scale (agree, undecided, disagree).