| Value | Category | Cases | |
|---|---|---|---|
| 1 | Not effective at all | 3 | 
                                    
                                    5.4%
                                 | 
| 2 | 3 | 
                                    
                                    5.4%
                                 | |
| 3 | 1 | 
                                    
                                    1.8%
                                 | |
| 4 | 2 | 
                                    
                                    3.6%
                                 | |
| 5 | 5 | 
                                    
                                    8.9%
                                 | |
| 6 | 4 | 
                                    
                                    7.1%
                                 | |
| 7 | 9 | 
                                    
                                    16.1%
                                 | |
| 8 | 12 | 
                                    
                                    21.4%
                                 | |
| 9 | 12 | 
                                    
                                    21.4%
                                 | |
| 10 | Very effective | 5 | 
                                    
                                    8.9%
                                 | 
| 11 | Don't know | 55 | |
| Sysmiss | 32 |