| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 | 
                                                                 
                                    
                                    0%
                                 
                                                             | 
                                                        
                    
| -7 | Does not apply | 5 | 
                                                                 
                                    
                                    2.4%
                                 
                                                             | 
                                                        
                    
| 0 | No obstacle | 87 | 
                                                                 
                                    
                                    41.6%
                                 
                                                             | 
                                                        
                    
| 1 | Minor obstacle | 91 | 
                                                                 
                                    
                                    43.5%
                                 
                                                             | 
                                                        
                    
| 2 | Moderate obstacle | 22 | 
                                                                 
                                    
                                    10.5%
                                 
                                                             | 
                                                        
                    
| 3 | Major obstacle | 1 | 
                                                                 
                                    
                                    0.5%
                                 
                                                             | 
                                                        
                    
| 4 | Very severe obstacle | 3 | 
                                                                 
                                    
                                    1.4%
                                 
                                                             |