| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 7 |
1.2%
|
| -7 | Does not apply | 2 |
0.3%
|
| 0 | No obstacle | 166 |
27.6%
|
| 1 | Minor obstacle | 126 |
21%
|
| 2 | Moderate obstacle | 191 |
31.8%
|
| 3 | Major obstacle | 99 |
16.5%
|
| 4 | Very severe obstacle | 10 |
1.7%
|