| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -7 | Does not apply | 7 |
4.7%
|
| 0 | No obstacle | 84 |
56%
|
| 1 | Minor obstacle | 36 |
24%
|
| 2 | Moderate obstacle | 15 |
10%
|
| 3 | Major obstacle | 4 |
2.7%
|
| 4 | Very severe obstacle | 4 |
2.7%
|