| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -7 | Does not apply | 0 |
0%
|
| 0 | No obstacle | 63 |
40.6%
|
| 1 | Minor obstacle | 46 |
29.7%
|
| 2 | Moderate obstacle | 27 |
17.4%
|
| 3 | Major obstacle | 18 |
11.6%
|
| 4 | Very severe obstacle | 1 |
0.6%
|