| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 5 |
13.5%
|
| 0 | None | 28 |
75.7%
|
| 1 | 1 |
2.7%
|
|
| 3 | 1 |
2.7%
|
|
| 10 | 1 |
2.7%
|
|
| 15 | 1 |
2.7%
|
|
| Sysmiss | 115 |