| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -7 | Does not apply | 0 |
0%
|
| 0 | No obstacle | 111 |
44.4%
|
| 1 | Minor obstacle | 86 |
34.4%
|
| 2 | Moderate obstacle | 38 |
15.2%
|
| 3 | Major obstacle | 11 |
4.4%
|
| 4 | Very severe obstacle | 4 |
1.6%
|