| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 6 |
1.6%
|
| -7 | Does not apply | 3 |
0.8%
|
| 0 | No obstacle | 73 |
19.4%
|
| 1 | Minor obstacle | 38 |
10.1%
|
| 2 | Moderate obstacle | 94 |
24.9%
|
| 3 | Major obstacle | 65 |
17.2%
|
| 4 | Very severe obstacle | 98 |
26%
|