| Value | Category | Cases | |
|---|---|---|---|
| -1 | Missing | 138 |
0.5%
|
| 0 | Never | 10150 |
36.6%
|
| 1 | Once or twice | 892 |
3.2%
|
| 2 | Several times | 576 |
2.1%
|
| 3 | Many times | 206 |
0.7%
|
| 7 | Not applicable/Saw no problems | 15112 |
54.5%
|
| 9 | Don't know | 639 |
2.3%
|
| 998 | Refused | 0 |
0%
|