| Value | Category |
|---|---|
| 1 | I don't use e-cigarettes |
| 2 | No, I don't use e-cigarettes or feel like using e-cigarettes the first thing in the morning |
| 3 | Yes, I sometimes use e-cigarettes or feel like using e-cigarettes the first thing in the morning |
| 4 | Yes, I always use e-cigarettes or feel like using e-cigarettes the first thing in the morning |
| Sysmiss |