| Value | Category | Cases | |
|---|---|---|---|
| 1 | Not effective at all | 2 |
1.7%
|
| 3 | 3 |
2.5%
|
|
| 4 | 5 |
4.1%
|
|
| 5 | 5 |
4.1%
|
|
| 6 | 10 |
8.3%
|
|
| 7 | 11 |
9.1%
|
|
| 8 | 18 |
14.9%
|
|
| 9 | 20 |
16.5%
|
|
| 10 | Very effective | 15 |
12.4%
|
| 11 | Don't know | 32 |
26.4%
|