| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -7 | Does not apply | 0 |
0%
|
| 0 | No obstacle | 180 |
31%
|
| 1 | Minor obstacle | 81 |
13.9%
|
| 2 | Moderate obstacle | 52 |
9%
|
| 3 | Major obstacle | 139 |
23.9%
|
| 4 | Very severe obstacle | 129 |
22.2%
|