| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 1 |
3.8%
|
| 1 | One month or less | 11 |
42.3%
|
| 2 | 4 |
15.4%
|
|
| 3 | 7 |
26.9%
|
|
| 4 | 1 |
3.8%
|
|
| 6 | 2 |
7.7%
|
|
| Sysmiss | 131 |