| Value | Category | Cases | |
|---|---|---|---|
| -1 | Missing | 5 |
0.4%
|
| 0 | Not at all effective | 124 |
10.3%
|
| 1 | Not very effective | 214 |
17.8%
|
| 2 | Somewhat effective | 422 |
35.2%
|
| 3 | Very effective | 415 |
34.6%
|
| 9 | Don't know | 19 |
1.6%
|
| 98 | Refused | 0 |
0%
|