| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 12 |
3.9%
|
| -7 | Does not apply | 76 |
24.4%
|
| 0 | No obstacle | 163 |
52.4%
|
| 1 | Minor obstacle | 22 |
7.1%
|
| 2 | Moderate obstacle | 17 |
5.5%
|
| 3 | Major obstacle | 11 |
3.5%
|
| 4 | Very severe obstacle | 10 |
3.2%
|