| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 1 |
0.3%
|
| -7 | Does not apply (spontaneous) | 8 |
2.2%
|
| 1 | Yes | 98 |
27.5%
|
| 2 | No | 250 |
70%
|
| Sysmiss | 1 |