Table 2.

System usability scale (SUS) scores and corresponding grades.

SUS scores			Percentile range		Adjective
Cycle 1: individual scores
	87.5	96-100		Best imaginable
	50	N/Aa		Poor
	62.5	15-34		OK or fair
	65	41-59		OK or fair
	55	N/A		OK or fair
	30	N/A		Worst imaginable
	65	41-59		OK or fair
Cycle 1 average score, mean (SD)
	59.3 (17.48)	15-34		OK or fair
Cycle 2: individual scores
	75	70-79		Good
	70	41-59		Good
Cycle 2 average score, mean (SD)
	72.5 (3.54)	60-64		Good
Overall score (cycles 1 and 2), mean (SD)
	62.2 (16.27)	15-34		OK or fair

^aN/A: not applicable.