| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -7 | Does not apply | 0 |
0%
|
| 0 | No obstacle | 101 |
41.1%
|
| 1 | Minor obstacle | 55 |
22.4%
|
| 2 | Moderate obstacle | 36 |
14.6%
|
| 3 | Major obstacle | 30 |
12.2%
|
| 4 | Very severe obstacle | 24 |
9.8%
|