| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 3 |
0.7%
|
| -7 | Does not apply | 14 |
3.4%
|
| 0 | No obstacle | 244 |
59.7%
|
| 1 | Minor obstacle | 71 |
17.4%
|
| 2 | Moderate obstacle | 60 |
14.7%
|
| 3 | Major obstacle | 10 |
2.4%
|
| 4 | Very severe obstacle | 7 |
1.7%
|