| Value | Category | Cases | |
|---|---|---|---|
| -99 | 12 | 
                                    
                                    4.1%
                                 | |
| 1 | Not effective at all | 17 | 
                                    
                                    5.8%
                                 | 
| 2 | 15 | 
                                    
                                    5.1%
                                 | |
| 3 | 13 | 
                                    
                                    4.4%
                                 | |
| 4 | 14 | 
                                    
                                    4.7%
                                 | |
| 5 | 19 | 
                                    
                                    6.4%
                                 | |
| 6 | 19 | 
                                    
                                    6.4%
                                 | |
| 7 | 21 | 
                                    
                                    7.1%
                                 | |
| 8 | 18 | 
                                    
                                    6.1%
                                 | |
| 9 | 15 | 
                                    
                                    5.1%
                                 | |
| 10 | Very effective | 35 | 
                                    
                                    11.9%
                                 | 
| 11 | Don't know | 97 | 
                                    
                                    32.9%
                                 | 
| Sysmiss | 31 |