| Value | Category |
|---|---|
| 1 | less than one cigarette per day |
| 2 | 1 cigarette per day |
| 3 | 2 to 5 cigarettes per day |
| 4 | 6 to 15 cigarettes per day (about ½ pack) |
| 5 | 16 to 25 cigarettes per day (about 1 pack) |
| 6 | 26 to 35 cigarettes per day (about 1 ½ packs) |
| 7 | more than 35 cigarettes per day (about 2 packs or more) |
| 9 | don't know/refuse to answer |