| Value | Category | Cases | |
|---|---|---|---|
| 1 | no difficulty remembering/concentrating | 11051 |
94.3%
|
| 2 | some difficulty | 508 |
4.3%
|
| 3 | a lot of difficulty | 136 |
1.2%
|
| 4 | cannot remember/concentrate at all | 23 |
0.2%
|
| 8 | don't know | 2 |
0%
|
| Sysmiss | 1229 |