| Value | Category | Cases | |
|---|---|---|---|
| 0 | no | 427 | 
                                                                 
                                    
                                    99.3%
                                 
                                                             | 
                                                        
                    
| 1 | yes: intravenous (iv | 3 | 
                                                                 
                                    
                                    0.7%
                                 
                                                             | 
                                                        
                    
| 8 | don't know | 0 | 
                                                                 
                                    
                                    0%
                                 
                                                             | 
                                                        
                    
| Sysmiss | 6325 |