| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 2 |
6.7%
|
| 0 | Less than 1 hour | 14 |
46.7%
|
| 1 | 3 |
10%
|
|
| 2 | 1 |
3.3%
|
|
| 5 | 5 |
16.7%
|
|
| 6 | 1 |
3.3%
|
|
| 7 | 1 |
3.3%
|
|
| 10 | 2 |
6.7%
|
|
| 20 | 1 |
3.3%
|
|
| Sysmiss | 321 |