| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 10 |
2.8%
|
| -7 | Does not apply | 14 |
4%
|
| 0 | No obstacle | 243 |
69%
|
| 1 | Minor obstacle | 65 |
18.5%
|
| 2 | Moderate obstacle | 14 |
4%
|
| 3 | Major obstacle | 6 |
1.7%
|
| 4 | Very severe obstacle | 0 |
0%
|