| Value | Category | Cases | |
|---|---|---|---|
| -99 | 7 | 
                                    
                                    2.3%
                                 | |
| 1 | Not effective at all | 12 | 
                                    
                                    3.9%
                                 | 
| 2 | 11 | 
                                    
                                    3.6%
                                 | |
| 3 | 22 | 
                                    
                                    7.2%
                                 | |
| 4 | 11 | 
                                    
                                    3.6%
                                 | |
| 5 | 30 | 
                                    
                                    9.9%
                                 | |
| 6 | 17 | 
                                    
                                    5.6%
                                 | |
| 7 | 32 | 
                                    
                                    10.5%
                                 | |
| 8 | 16 | 
                                    
                                    5.3%
                                 | |
| 9 | 16 | 
                                    
                                    5.3%
                                 | |
| 10 | Very effective | 40 | 
                                    
                                    13.2%
                                 | 
| 11 | Don't know | 90 | 
                                    
                                    29.6%
                                 | 
| Sysmiss | 22 |