| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 10 | 
                                    
                                    5.6%
                                 | 
| 1 | Yes | 136 | 
                                    
                                    76.8%
                                 | 
| 2 | No | 31 | 
                                    
                                    17.5%
                                 | 
| Sysmiss | 778 |