| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -7 | Does not apply | 0 |
0%
|
| 0 | No obstacle | 102 |
28.3%
|
| 1 | Minor obstacle | 53 |
14.7%
|
| 2 | Moderate obstacle | 104 |
28.9%
|
| 3 | Major obstacle | 66 |
18.3%
|
| 4 | Very severe obstacle | 35 |
9.7%
|