| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 8 |
2.6%
|
| -7 | Does not apply | 3 |
1%
|
| 0 | No obstacle | 93 |
30.3%
|
| 1 | Minor obstacle | 80 |
26.1%
|
| 2 | Moderate obstacle | 57 |
18.6%
|
| 3 | Major obstacle | 40 |
13%
|
| 4 | Very severe obstacle | 26 |
8.5%
|