| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 2 |
0.6%
|
| -7 | Does not apply | 5 |
1.4%
|
| 0 | No obstacle | 121 |
33.9%
|
| 1 | Minor obstacle | 88 |
24.6%
|
| 2 | Moderate obstacle | 90 |
25.2%
|
| 3 | Major obstacle | 32 |
9%
|
| 4 | Very severe obstacle | 19 |
5.3%
|