| Value | Category | Cases | |
|---|---|---|---|
| -1 | Missing | 10 |
0.8%
|
| 0 | Never | 372 |
31%
|
| 1 | Once or twice | 144 |
12%
|
| 2 | Several times | 175 |
14.6%
|
| 3 | Many times | 26 |
2.2%
|
| 7 | Not applicable/Saw no problems | 469 |
39.1%
|
| 9 | Don't know | 4 |
0.3%
|