| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 35 |
2.5%
|
| -7 | Does not apply (spontaneous) | 59 |
4.2%
|
| 1 | Yes | 365 |
25.8%
|
| 2 | No | 954 |
67.5%
|
| Sysmiss | 33 |