| Value | Category | Cases | |
|---|---|---|---|
| -99 | 11 | 
                                    
                                    3.8%
                                 | |
| 1 | Not effective at all | 10 | 
                                    
                                    3.4%
                                 | 
| 2 | 18 | 
                                    
                                    6.2%
                                 | |
| 3 | 28 | 
                                    
                                    9.6%
                                 | |
| 4 | 15 | 
                                    
                                    5.2%
                                 | |
| 5 | 21 | 
                                    
                                    7.2%
                                 | |
| 6 | 20 | 
                                    
                                    6.9%
                                 | |
| 7 | 14 | 
                                    
                                    4.8%
                                 | |
| 8 | 15 | 
                                    
                                    5.2%
                                 | |
| 9 | 13 | 
                                    
                                    4.5%
                                 | |
| 10 | Very effective | 19 | 
                                    
                                    6.5%
                                 | 
| 11 | Don't know | 107 | 
                                    
                                    36.8%
                                 | 
| Sysmiss | 35 |