| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -7 | Does not apply | 3 |
2.1%
|
| 0 | No obstacle | 30 |
20.7%
|
| 1 | Minor obstacle | 23 |
15.9%
|
| 2 | Moderate obstacle | 44 |
30.3%
|
| 3 | Major obstacle | 32 |
22.1%
|
| 4 | Very severe obstacle | 13 |
9%
|