| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -7 | Does not apply | 2 |
0.3%
|
| 0 | No obstacle | 467 |
77.8%
|
| 1 | Minor obstacle | 61 |
10.2%
|
| 2 | Moderate obstacle | 34 |
5.7%
|
| 3 | Major obstacle | 18 |
3%
|
| 4 | Very severe obstacle | 18 |
3%
|