| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 5 |
1.1%
|
| -7 | Does not apply (spontaneous) | 1 |
0.2%
|
| 1 | Yes | 71 |
15%
|
| 2 | No | 397 |
83.8%
|