| Value | Category | Cases | |
|---|---|---|---|
| 1 | Not effective at all | 5 | 
                                    
                                    11.4%
                                 | 
| 2 | 2 | 
                                    
                                    4.5%
                                 | |
| 3 | 2 | 
                                    
                                    4.5%
                                 | |
| 4 | 1 | 
                                    
                                    2.3%
                                 | |
| 5 | 7 | 
                                    
                                    15.9%
                                 | |
| 6 | 3 | 
                                    
                                    6.8%
                                 | |
| 7 | 6 | 
                                    
                                    13.6%
                                 | |
| 8 | 9 | 
                                    
                                    20.5%
                                 | |
| 9 | 8 | 
                                    
                                    18.2%
                                 | |
| 10 | Very effective | 1 | 
                                    
                                    2.3%
                                 | 
| 11 | Don't know | 66 | |
| Sysmiss | 33 |