| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| 1 | In-house | 82 |
65.1%
|
| 2 | External | 18 |
14.3%
|
| 3 | Both | 26 |
20.6%
|
| Sysmiss | 475 |