| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 11 |
3%
|
| -7 | Does not apply | 0 |
0%
|
| 0 | No obstacle | 40 |
11%
|
| 1 | Minor obstacle | 52 |
14.2%
|
| 2 | Moderate obstacle | 95 |
26%
|
| 3 | Major obstacle | 84 |
23%
|
| 4 | Very severe obstacle | 83 |
22.7%
|