| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 5 |
1.2%
|
| -7 | Does not apply | 11 |
2.6%
|
| 0 | No obstacle | 136 |
31.7%
|
| 1 | Minor obstacle | 82 |
19.1%
|
| 2 | Moderate obstacle | 167 |
38.9%
|
| 3 | Major obstacle | 22 |
5.1%
|
| 4 | Very severe obstacle | 6 |
1.4%
|