| Value | Category | Cases | |
|---|---|---|---|
| 1 | Not effective at all | 5 | 
                                    
                                    1.7%
                                 | 
| 2 | 10 | 
                                    
                                    3.4%
                                 | |
| 3 | 13 | 
                                    
                                    4.4%
                                 | |
| 4 | 14 | 
                                    
                                    4.8%
                                 | |
| 5 | 45 | 
                                    
                                    15.4%
                                 | |
| 6 | 37 | 
                                    
                                    12.6%
                                 | |
| 7 | 25 | 
                                    
                                    8.5%
                                 | |
| 8 | 17 | 
                                    
                                    5.8%
                                 | |
| 9 | 9 | 
                                    
                                    3.1%
                                 | |
| 10 | Very effective | 6 | 
                                    
                                    2%
                                 | 
| 11 | Don't know | 112 | 
                                    
                                    38.2%
                                 | 
| Sysmiss | 8 |