| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -7 | Does not apply | 5 |
4.2%
|
| 0 | No obstacle | 54 |
45%
|
| 1 | Minor obstacle | 14 |
11.7%
|
| 2 | Moderate obstacle | 25 |
20.8%
|
| 3 | Major obstacle | 17 |
14.2%
|
| 4 | Very severe obstacle | 5 |
4.2%
|