| Value | Category | Cases | |
|---|---|---|---|
| 1 | Not effective at all | 1 |
0.4%
|
| 2 | 3 |
1.3%
|
|
| 3 | 2 |
0.9%
|
|
| 4 | 8 |
3.4%
|
|
| 5 | 15 |
6.4%
|
|
| 6 | 23 |
9.9%
|
|
| 7 | 36 |
15.5%
|
|
| 8 | 40 |
17.2%
|
|
| 9 | 31 |
13.3%
|
|
| 10 | Very effective | 33 |
14.2%
|
| 11 | Don't know | 41 |
17.6%
|
| Sysmiss | 4 |