| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 3 |
2%
|
| -7 | Does not apply | 4 |
2.7%
|
| 0 | No obstacle | 25 |
16.8%
|
| 1 | Minor obstacle | 22 |
14.8%
|
| 2 | Moderate obstacle | 10 |
6.7%
|
| 3 | Major obstacle | 27 |
18.1%
|
| 4 | Very severe obstacle | 58 |
38.9%
|