| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 44 | 
                                                                 
                                    
                                    0.5%
                                 
                                                             | 
                                                        
                    
| -7 | Not applicable (spontaneous) | 84 | 
                                                                 
                                    
                                    0.9%
                                 
                                                             | 
                                                        
                    
| 1 | Yes | 4450 | 
                                                                 
                                    
                                    48.5%
                                 
                                                             | 
                                                        
                    
| 2 | No | 4590 | 
                                                                 
                                    
                                    50.1%
                                 
                                                             | 
                                                        
                    
| Sysmiss | 1504 |