| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 18 |
1.8%
|
| -7 | Does not apply | 35 |
3.5%
|
| 0 | No obstacle | 678 |
67.3%
|
| 1 | Minor obstacle | 193 |
19.1%
|
| 2 | Moderate obstacle | 45 |
4.5%
|
| 3 | Major obstacle | 30 |
3%
|
| 4 | Very severe obstacle | 9 |
0.9%
|