| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 5 |
0.8%
|
| -7 | Does not apply (spontaneous) | 15 |
2.5%
|
| 1 | Yes | 17 |
2.8%
|
| 2 | No | 561 |
93.8%
|