| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 2 |
1.3%
|
| -7 | Does not apply | 0 |
0%
|
| 0 | No obstacle | 11 |
7.4%
|
| 1 | Minor obstacle | 37 |
24.8%
|
| 2 | Moderate obstacle | 35 |
23.5%
|
| 3 | Major obstacle | 18 |
12.1%
|
| 4 | Very severe obstacle | 46 |
30.9%
|