| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -7 | Does not apply | 0 |
0%
|
| 0 | No obstacle | 178 |
34.3%
|
| 1 | Minor obstacle | 96 |
18.5%
|
| 2 | Moderate obstacle | 194 |
37.4%
|
| 3 | Major obstacle | 51 |
9.8%
|
| 4 | Very severe obstacle | 0 |
0%
|