| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -7 | Does not apply | 0 |
0%
|
| 0 | No obstacle | 364 |
90.1%
|
| 1 | Minor obstacle | 12 |
3%
|
| 2 | Moderate obstacle | 17 |
4.2%
|
| 3 | Major obstacle | 5 |
1.2%
|
| 4 | Very severe obstacle | 6 |
1.5%
|