| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -7 | Does not apply | 0 |
0%
|
| 0 | No obstacle | 124 |
34.6%
|
| 1 | Minor obstacle | 71 |
19.8%
|
| 2 | Moderate obstacle | 82 |
22.9%
|
| 3 | Major obstacle | 64 |
17.9%
|
| 4 | Very severe obstacle | 17 |
4.7%
|