| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 3 |
2.1%
|
| -7 | Does not apply | 3 |
2.1%
|
| 0 | No obstacle | 52 |
35.9%
|
| 1 | Minor obstacle | 19 |
13.1%
|
| 2 | Moderate obstacle | 49 |
33.8%
|
| 3 | Major obstacle | 15 |
10.3%
|
| 4 | Very severe obstacle | 4 |
2.8%
|