| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -7 | Does not apply | 0 |
0%
|
| 0 | No obstacle | 80 |
32%
|
| 1 | Minor obstacle | 67 |
26.8%
|
| 2 | Moderate obstacle | 72 |
28.8%
|
| 3 | Major obstacle | 31 |
12.4%
|
| 4 | Very severe obstacle | 0 |
0%
|