| Value | Category | Cases | |
|---|---|---|---|
| 1 | Highly effective | 1294 |
10.9%
|
| 2 | Moderately effective | 3741 |
31.6%
|
| 3 | Ineffective | 972 |
8.2%
|
| 4 | Don't know | 5820 |
49.2%
|