| Value | Category | Cases | |
|---|---|---|---|
| 1 | Not effective at all | 4 | 
                                    
                                    8.5%
                                 | 
| 2 | 6 | 
                                    
                                    12.8%
                                 | |
| 3 | 4 | 
                                    
                                    8.5%
                                 | |
| 4 | 3 | 
                                    
                                    6.4%
                                 | |
| 5 | 8 | 
                                    
                                    17%
                                 | |
| 6 | 2 | 
                                    
                                    4.3%
                                 | |
| 7 | 5 | 
                                    
                                    10.6%
                                 | |
| 8 | 8 | 
                                    
                                    17%
                                 | |
| 9 | 6 | 
                                    
                                    12.8%
                                 | |
| 10 | Very effective | 1 | 
                                    
                                    2.1%
                                 | 
| 11 | Don't know | 60 | |
| Sysmiss | 36 |