| Value | Category | 
                                    
                    
                        | 1 | Weekly | 
                                    
                    
                        | 2 | Biweekly | 
                                    
                    
                        | 3 | Monthly | 
                                    
                    
                        | 4 | Biannually | 
                                    
                    
                        | 5 | Annually | 
                                    
                    
                        | 6 | Never | 
                                    
                    
                        | 7 | Other, Please specify | 
                                    
                    
                        | 8 | Every two weeks | 
                                    
                    
                        | 9 | Bi monthly | 
                                    
                    
                        | 10 | Once | 
                                    
                    
                        | 999 | Missing | 
                            
            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.