Table 5.
Comparison between spectrophotometric and digital or photographic methods using Wilcoxon signed rank test
| N | Mean | Std. deviation | Mini mum | Maxi mum | Z Value | P Value | |
|---|---|---|---|---|---|---|---|
| Spectrophotometric methods L | 50 | 78.3 | 5.89 | 63.7 | 87.4 | –0.155 | 0.877 |
| Digital or photographic methods L | 50 | 78.4 | 5.66 | 66.1 | 85.9 | ||
| Spectrophotometric methods a | 50 | –0.9 | 1.74 | –3 | 4.6 | –1.166 | 0.244 |
| Digital or photographic methods a | 50 | –0.6 | 1.85 | –3 | 4.3 | ||
| Spectrophotometric methods b | 50 | 15.2 | 5.38 | 9.4 | 33 | –2.314 | 0.021* |
| Digital or photographic methods b | 50 | 14.9 | 5.28 | 8 | 32.1 |
*P < 0.05