| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -7 | Does not apply | 0 |
0%
|
| 0 | No obstacle | 23 |
14.6%
|
| 1 | Minor obstacle | 25 |
15.9%
|
| 2 | Moderate obstacle | 39 |
24.8%
|
| 3 | Major obstacle | 42 |
26.8%
|
| 4 | Very severe obstacle | 28 |
17.8%
|