Table 2.
Summary of pairwise Wilcoxon signed-rank tests for perception and preference ratings.
| Perceptual dimension | Pairwise comparison | Standardized test statistic | P value | Significant difference at P<.017? |
| Comprehensibility | Text, text + images | –4.27 | <.001 | Yes |
|
|
Text, narration + images | –3.11 | .002 | Yes |
|
|
Narration + images, text + images | –2.61 | .009 | Yes |
| Utility | Text, text + images | –2.32 | .021 | No |
|
|
Text, narration + images | –1.18 | .236 | No |
|
|
Narration + images, text + images | –2.17 | .030 | No |
| Design quality | Text, text + images | –4.53 | <.001 | Yes |
|
|
Text, narration + images | –4.50 | <.001 | Yes |
|
|
Narration + images, text + images | –2.53 | .011 | Yes |
| Overall preference ranking | Text, text + images | –4.20 | <.001 | Yes |
|
|
Text, narration + images | –1.57 | .116 | No |
|
|
Narration + images, text + images | –3.72 | <.001 | Yes |