| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -7 | Does not apply | 3 |
2.5%
|
| 0 | No obstacle | 68 |
56.7%
|
| 1 | Minor obstacle | 14 |
11.7%
|
| 2 | Moderate obstacle | 7 |
5.8%
|
| 3 | Major obstacle | 19 |
15.8%
|
| 4 | Very severe obstacle | 9 |
7.5%
|