| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -7 | Does not apply | 2 |
0.6%
|
| 0 | No obstacle | 82 |
23.8%
|
| 1 | Minor obstacle | 43 |
12.5%
|
| 2 | Moderate obstacle | 78 |
22.6%
|
| 3 | Major obstacle | 58 |
16.8%
|
| 4 | Very severe obstacle | 82 |
23.8%
|