| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 5 |
0.8%
|
| -7 | Does not apply | 69 |
10.6%
|
| 0 | No obstacle | 231 |
35.6%
|
| 1 | Minor obstacle | 89 |
13.7%
|
| 2 | Moderate obstacle | 87 |
13.4%
|
| 3 | Major obstacle | 79 |
12.2%
|
| 4 | Very severe obstacle | 89 |
13.7%
|