| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 4 | 
                                    
                                    8.7%
                                 | 
| 1 | Yes | 24 | 
                                    
                                    52.2%
                                 | 
| 2 | No | 18 | 
                                    
                                    39.1%
                                 | 
| Sysmiss | 51 |