| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 1 |
0.7%
|
| -7 | Does not apply | 0 |
0%
|
| 0 | No obstacle | 28 |
18.8%
|
| 1 | Minor obstacle | 66 |
44.3%
|
| 2 | Moderate obstacle | 39 |
26.2%
|
| 3 | Major obstacle | 12 |
8.1%
|
| 4 | Very severe obstacle | 3 |
2%
|