| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 3 |
0.7%
|
| -7 | Does not apply (spontaneous) | 22 |
5.5%
|
| 1 | Yes | 76 |
19%
|
| 2 | No | 300 |
74.8%
|
| Sysmiss | 8 |