| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 | 
                                    
                                    0%
                                 | 
| -7 | Does not apply (sponatneous) | 24 | 
                                    
                                    2.3%
                                 | 
| 1 | Yes | 122 | 
                                    
                                    11.9%
                                 | 
| 2 | No | 878 | 
                                    
                                    85.7%
                                 |