| Value | Category | 
                                    
                    
                        | 1 | INVOLVED, IMPORTANT | 
                                    
                    
                        | 2 | INVOLVED, NOT IMPORTANT | 
                                    
                    
                        | 3 | NOT INVOLVED | 
                                    
                    
                        | 4 | METHOD NOT APPLICABLE | 
                                    
                    
                        | 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.