| Value | Category |
|---|---|
| -5 | less than one year |
| -4 | missing data |
| -3 | refused to answer |
| -2 | not applicable |
| -1 | do not know |
| 1 | matric |
| 2 | diploma |
| 3 | university (ba/bs) |
| 4 | masters (m.a/m.s) |
| 5 | ph.d/d.ed |
| 7 | f.de - physical science |
| 8 | national institute for learning disabilities |