| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 2 |
5.7%
|
| 0 | Less than 1 hour | 7 |
20%
|
| 1 | 3 |
8.6%
|
|
| 2 | 9 |
25.7%
|
|
| 3 | 9 |
25.7%
|
|
| 4 | 3 |
8.6%
|
|
| 5 | 2 |
5.7%
|
|
| Sysmiss | 329 |