| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 4 |
1.1%
|
| -7 | Does not apply (spontaneous) | 16 |
4.5%
|
| 1 | Yes | 39 |
10.9%
|
| 2 | No | 298 |
83.5%
|
| Sysmiss | 1 |