Time | Grouping | n | 0 level | 1 level | 2 level | 3 level | 4 level |
Prior treatment | Observation group | 90 | 0 | 15 | 39 | 24 | 12 |
Control group | 90 | 0 | 16 | 37 | 26 | 11 | |
Z value |
| 0.041 | |||||
P value |
| 0.968 | |||||
Posttreatment | Observation group | 90 | 11 | 29 | 30 | 15 | 5 |
control group | 90 | 5 | 23 | 32 | 22 | 8 | |
Z value |
| 2.040 | |||||
P value |
| 0.042 |