| Value | Category | Cases | |
|---|---|---|---|
| -9 | NIU (not in universe) | 124 |
5.4%
|
| 1 | yes, effective at preventing pregnancy | 1598 |
69%
|
| 2 | no, not effective at preventing pregnancy | 560 |
24.2%
|
| 98 | don't know | 34 |
1.5%
|
| 9999995 | missing:impute | 0 |
0%
|
| Sysmiss | 467 |