| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 10 |
1%
|
| -7 | Does not apply | 14 |
1.4%
|
| 0 | No obstacle | 608 |
59.1%
|
| 1 | Minor obstacle | 233 |
22.7%
|
| 2 | Moderate obstacle | 117 |
11.4%
|
| 3 | Major obstacle | 41 |
4%
|
| 4 | Very severe obstacle | 5 |
0.5%
|