| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 4 |
0.7%
|
| -7 | Does not apply (spontaneous) | 3 |
0.5%
|
| 1 | Yes | 78 |
13%
|
| 2 | No | 515 |
85.8%
|