| Value | Category | 
                                    
                    
                        | 3 | 3. Days | 
                                    
                    
                        | 4 | 4. Weeks | 
                                    
                    
                        | 5 | 5. Months | 
                                    
                    
                        | 95 | 95. Out of range | 
                                    
                    
                        | 96 | 96. Still ill | 
                                    
                    
                        | 98 | 98. DK | 
                                    
                    
                        | 99 | 99. Miss | 
                                    
                    
                        | Sysmiss |  | 
                            
            Warning: these figures indicate the number of cases found in the data file. They cannot be interpreted as summary statistics of the population of interest.