| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 3 | 
                                                                 
                                    
                                    0.5%
                                 
                                                             | 
                                                        
                    
| 1 | Yes | 20 | 
                                                                 
                                    
                                    3.3%
                                 
                                                             | 
                                                        
                    
| 2 | No | 586 | 
                                                                 
                                    
                                    96.2%
                                 
                                                             |