| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 49 |
18.1%
|
| -7 | Does not apply | 0 |
0%
|
| 0 | No obstacle | 26 |
9.6%
|
| 1 | Minor obstacle | 39 |
14.4%
|
| 2 | Moderate obstacle | 66 |
24.4%
|
| 3 | Major obstacle | 63 |
23.2%
|
| 4 | Very severe obstacle | 28 |
10.3%
|