| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 3 |
2.7%
|
| -7 | Does not apply | 1 |
0.9%
|
| 0 | No obstacle | 54 |
48.6%
|
| 1 | Minor obstacle | 36 |
32.4%
|
| 2 | Moderate obstacle | 7 |
6.3%
|
| 3 | Major obstacle | 10 |
9%
|
| 4 | Very severe obstacle | 0 |
0%
|