| Value | Category | Cases | |
|---|---|---|---|
| -1 | Missing | 0 |
0%
|
| 0 | Never | 318 |
25.8%
|
| 1 | Once or twice | 29 |
2.4%
|
| 2 | Several times | 20 |
1.6%
|
| 3 | Many times | 15 |
1.2%
|
| 7 | Not applicable/Saw no problems | 839 |
68.1%
|
| 9 | Don't know | 11 |
0.9%
|
| 998 | Refused | 0 |
0%
|