| Value | Category | Cases | |
|---|---|---|---|
| 1 | Not effective at all | 4 | 
                                    
                                    1.9%
                                 | 
| 2 | 1 | 
                                    
                                    0.5%
                                 | |
| 3 | 10 | 
                                    
                                    4.7%
                                 | |
| 4 | 10 | 
                                    
                                    4.7%
                                 | |
| 5 | 28 | 
                                    
                                    13.3%
                                 | |
| 6 | 22 | 
                                    
                                    10.4%
                                 | |
| 7 | 29 | 
                                    
                                    13.7%
                                 | |
| 8 | 30 | 
                                    
                                    14.2%
                                 | |
| 9 | 24 | 
                                    
                                    11.4%
                                 | |
| 10 | Very effective | 53 | 
                                    
                                    25.1%
                                 | 
| 11 | Don't know | 52 | |
| Sysmiss | 56 |