| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 1 |
0.2%
|
| -7 | Does not apply | 0 |
0%
|
| 0 | No obstacle | 179 |
29.7%
|
| 1 | Minor obstacle | 186 |
30.8%
|
| 2 | Moderate obstacle | 87 |
14.4%
|
| 3 | Major obstacle | 119 |
19.7%
|
| 4 | Very severe obstacle | 31 |
5.1%
|