| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 3 |
0.8%
|
| -7 | Does not apply | 0 |
0%
|
| 0 | No obstacle | 187 |
51.8%
|
| 1 | Minor obstacle | 67 |
18.6%
|
| 2 | Moderate obstacle | 87 |
24.1%
|
| 3 | Major obstacle | 11 |
3%
|
| 4 | Very severe obstacle | 6 |
1.7%
|