| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 1 |
0.2%
|
| 1 | Never | 31 |
5.2%
|
| 2 | Rarely | 95 |
15.8%
|
| 3 | Sometimes | 287 |
47.8%
|
| 4 | Frequently | 187 |
31.1%
|