| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 2 |
0.5%
|
| -7 | Does not apply (spontaneous) | 35 |
9.3%
|
| 1 | Yes | 87 |
23.1%
|
| 2 | No | 252 |
67%
|
| Sysmiss | 1 |