Table 6 Descriptive data for mean RID0 (baseline) according to the difficulty index (DI)
| DI | N | Minimum | Maximum | Mean | SD |
|---|---|---|---|---|---|
| 5 | 5 | 6.38 | 9.50 | 7.78 | 1.33 |
| 6 | 11 | 5.24 | 12.49 | 9.17 | 2.15 |
| 7 | 8 | 5.58 | 13.51 | 9.86 | 2.70 |
| 8 | 5 | 8.12 | 12.70 | 10.91 | 1.47 |
| DI | N | Minimum | Maximum | Mean | SD |
|---|---|---|---|---|---|
| 5 | 5 | 6.38 | 9.50 | 7.78 | 1.33 |
| 6 | 11 | 5.24 | 12.49 | 9.17 | 2.15 |
| 7 | 8 | 5.58 | 13.51 | 9.86 | 2.70 |
| 8 | 5 | 8.12 | 12.70 | 10.91 | 1.47 |