| Value | Category | Cases | |
|---|---|---|---|
| -1 | Missing | 0 |
0%
|
| 0 | Never | 136 |
11.3%
|
| 1 | Once or twice | 193 |
16.1%
|
| 2 | Several times | 165 |
13.8%
|
| 3 | Many times | 66 |
5.5%
|
| 7 | Not applicable/Saw no problems | 638 |
53.2%
|
| 9 | Don't know | 2 |
0.2%
|
| 998 | Refused | 0 |
0%
|