| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 4 | 
                                                                 
                                    
                                    0.7%
                                 
                                                             | 
                                                        
                    
| 1 | Yes | 104 | 
                                                                 
                                    
                                    17.1%
                                 
                                                             | 
                                                        
                    
| 2 | No | 501 | 
                                                                 
                                    
                                    82.3%
                                 
                                                             |