| Value | Category | Cases | |
|---|---|---|---|
| 1 | Not effective at all | 1 |
0.6%
|
| 10 | Very effective | 3 |
1.8%
|
| 11 | Don't know | 82 |
48.5%
|
| -99 | 11 |
6.5%
|
|
| 2 | 3 |
1.8%
|
|
| 3 | 3 |
1.8%
|
|
| 4 | 5 |
3%
|
|
| 5 | 15 |
8.9%
|
|
| 6 | 13 |
7.7%
|
|
| 7 | 13 |
7.7%
|
|
| 8 | 13 |
7.7%
|
|
| 9 | 7 |
4.1%
|
|
| Sysmiss | 22 |