| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -7 | Does not apply | 6 |
2.4%
|
| 0 | No obstacle | 145 |
58%
|
| 1 | Minor obstacle | 67 |
26.8%
|
| 2 | Moderate obstacle | 21 |
8.4%
|
| 3 | Major obstacle | 11 |
4.4%
|
| 4 | Very severe obstacle | 0 |
0%
|