| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -7 | Does not apply | 1 |
0.2%
|
| 0 | No obstacle | 239 |
40.4%
|
| 1 | Minor obstacle | 39 |
6.6%
|
| 2 | Moderate obstacle | 110 |
18.6%
|
| 3 | Major obstacle | 141 |
23.8%
|
| 4 | Very severe obstacle | 62 |
10.5%
|