| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -7 | Does not apply | 0 |
0%
|
| 0 | No obstacle | 362 |
62.2%
|
| 1 | Minor obstacle | 133 |
22.9%
|
| 2 | Moderate obstacle | 55 |
9.5%
|
| 3 | Major obstacle | 27 |
4.6%
|
| 4 | Very severe obstacle | 5 |
0.9%
|