| Value | Category |
|---|---|
| -9 | Missing |
| -8 | Uncodeabel |
| -7 | N/a |
| 0 | I am not familiar with this technique |
| 1 | Within the last year |
| 2 | Within the last five years (2002-2007) |
| 3 | More than five years ago |
| 4 | I am not practicing this technique |
| 5 | Not practising this technique but knows |