| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 3 |
1.9%
|
| -7 | Does not apply | 12 |
7.6%
|
| 0 | No obstacle | 104 |
66.2%
|
| 1 | Minor obstacle | 22 |
14%
|
| 2 | Moderate obstacle | 7 |
4.5%
|
| 3 | Major obstacle | 4 |
2.5%
|
| 4 | Very severe obstacle | 5 |
3.2%
|