| Value | Category | Cases | |
|---|---|---|---|
| 0 | measured | 1722 | 
                                                                 
                                    
                                    94.4%
                                 
                                                             | 
                                                        
                    
| 3 | not present | 39 | 
                                                                 
                                    
                                    2.1%
                                 
                                                             | 
                                                        
                    
| 4 | refused | 61 | 
                                                                 
                                    
                                    3.3%
                                 
                                                             | 
                                                        
                    
| 6 | other | 3 | 
                                                                 
                                    
                                    0.2%
                                 
                                                             | 
                                                        
                    
| Sysmiss | 4656 |