| Value | Category |
|---|---|
| -999 | Refuse to answer |
| -222 | Interview declined |
| 1 | None |
| 2 | Some primary school |
| 3 | Primary school |
| 4 | Middle/JSS/JHS |
| 5 | SSS/SHS |
| 6 | O/A level |
| 7 | Voc./Tech./Commercial |
| 8 | Post-secondary certificates |
| 9 | Diploma/HND |
| 10 | Bachelor degree |
| 11 | Master’s |
| 12 | PhD |
| 13 | Others (specify) |
| Sysmiss |