| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 3 |
0.8%
|
| -7 | Does not apply | 5 |
1.4%
|
| 0 | No obstacle | 134 |
37.2%
|
| 1 | Minor obstacle | 36 |
10%
|
| 2 | Moderate obstacle | 61 |
16.9%
|
| 3 | Major obstacle | 44 |
12.2%
|
| 4 | Very severe obstacle | 77 |
21.4%
|