| Usability attribute | No. of items | Cronbach’s Alpha |
| Consistency | 6 | 0.947 |
| Visibility | 4 | 0.903 |
| Match | 3 | 0.901 |
| Minimalist | 4 | 0.919 |
| Memory | 5 | 0.934 |
| Feedback | 4 | 0.907 |
| Flexibility | 3 | 0.877 |
| Message | 4 | 0.909 |
| Error | 5 | 0.902 |
| Closure | 3 | 0.913 |
| Undo | 4 | 0.864 |
| Language | 4 | 0.84 |
| Control | 2 | 0.843 |
| Document | 2 | 0.869 |