Table 1:
Schedule of reduction and study visits.
| Study Visit: | Initial | b0 | b1 | b2 | b3 | c4 |
|---|---|---|---|---|---|---|
| aWeek 0 | Week 1 | Week 2 | Week 3 | Week 4 | ||
| Transitioned to VLNC cigarettes | Cigarettes/day | Ad lib | 100% of Week 0 | 100% of Week 0 | 100% of Week 0 | 100% of Week 0 |
| Nicotine content | 100% (17.6 mg) | 70% (12.3 mg) | 35% (6.3 mg) | 15% (2.3 mg) | 3% (0.6 mg) | |
| Reduced number of full nicotine CPD | Cigarettes/day | Ad lib | 70% of Week 0 | 35% of Week 0 | 15% of Week 0 | d3% of Week 0 |
| Nicotine content | 100% (17.6 mg) | 100% (17.6 mg) | 100% (17.6 mg) | 100% (17.6 mg) | 100% (17.6 mg) |
Baseline cigarettes/day established during this time;
Laboratory visits when participants received 21-mg nicotine replacement therapy patches and instructions to use one patch per day;
Laboratory visit when participants were advised to quit;
Participants received a minimum of 1 cigarette/day;
CPD=Cigarettes per day; mg/g=Milligram nicotine per gram tobacco; VLNC=Very low nicotine content. The presented nicotine contents reflect the ratings by RTI International for the batches of Spectrum cigarettes used in this trial (see Table S3). In the VLNC condition, study cigarettes at week 0 = NRC601, week 1 = NRC501, week 2 = NRC401, week 3 = NRC301, and week 4 = NRC103. In the CPD condition study cigarettes for all weeks = NRC601. Participants completed an online follow-up survey 1 month after the end of week 4