| Value | Category | Cases | |
|---|---|---|---|
| -1 | Missing | 0 |
0%
|
| 0 | Never | 120 |
8.9%
|
| 1 | Once or twice | 26 |
1.9%
|
| 2 | Several times | 34 |
2.5%
|
| 3 | Many times | 16 |
1.2%
|
| 7 | Not applicable/Saw no problems | 863 |
63.9%
|
| 9 | Don't know | 291 |
21.6%
|
| 998 | Refused | 0 |
0%
|