| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -7 | Does not apply | 0 |
0%
|
| 0 | No obstacle | 269 |
66.6%
|
| 1 | Minor obstacle | 58 |
14.4%
|
| 2 | Moderate obstacle | 51 |
12.6%
|
| 3 | Major obstacle | 11 |
2.7%
|
| 4 | Very severe obstacle | 15 |
3.7%
|