| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -7 | Does not apply | 0 |
0%
|
| 0 | No obstacle | 63 |
28.8%
|
| 1 | Minor obstacle | 42 |
19.2%
|
| 2 | Moderate obstacle | 29 |
13.2%
|
| 3 | Major obstacle | 50 |
22.8%
|
| 4 | Very severe obstacle | 35 |
16%
|