| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -7 | Does not apply | 3 |
0.5%
|
| 0 | No obstacle | 134 |
21.8%
|
| 1 | Minor obstacle | 131 |
21.3%
|
| 2 | Moderate obstacle | 166 |
27%
|
| 3 | Major obstacle | 132 |
21.5%
|
| 4 | Very severe obstacle | 49 |
8%
|