| Value | Category | Cases | |
|---|---|---|---|
| -1 | Missing | 1 |
0.1%
|
| 0 | Never | 395 |
32.9%
|
| 1 | Once or twice | 116 |
9.7%
|
| 2 | Several times | 143 |
11.9%
|
| 3 | Many times | 47 |
3.9%
|
| 7 | Not applicable/Saw no problems | 491 |
40.9%
|
| 9 | Don't know | 7 |
0.6%
|
| 998 | Refused | 0 |
0%
|