Sources & notes
Fillo keeps the ten English SUS items and five-point scale, with the documented “awkward” variant in item 8. The page breaks are Fillo’s adaptation. Credit John Brooke’s SUS in published reports; the instrument is © Digital Equipment Corporation, 1986.
- SUS: A ‘quick and dirty’ usability scaleJohn Brooke, in Usability Evaluation in Industry · 1996
- The Factor Structure of the System Usability Scale — wording guidance in section 5.2James R. Lewis and Jeff Sauro / HCI International · 2009
After product use or a usability session, before discussing the experience with the participant.
For complete responses: subtract 1 from odd-numbered answers; subtract even-numbered answers from 5. Add the results and multiply by 2.5. Report sample size and uncertainty. A score of 80 does not mean 80% satisfied; individual items are not diagnostic scales.
System Usability Scale (SUS)Keep the ten statements, order, five-point agreement scale, and pre-debrief timing. Item 8 uses ‘awkward’. Report one composite, not a separate learnability subscale.