| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -7 | Does not apply | 16 |
4%
|
| 0 | No obstacle | 136 |
33.8%
|
| 1 | Minor obstacle | 119 |
29.6%
|
| 2 | Moderate obstacle | 50 |
12.4%
|
| 3 | Major obstacle | 47 |
11.7%
|
| 4 | Very severe obstacle | 34 |
8.5%
|