Table 1.
Sample characteristics for respondents in the three wave-to-wave transitions
| Waves 3–4, n = 5,369 | Waves 4–5, n = 4,843 | Waves 5–6, n = 4,988 | |
| Age (years): M (SD) | 46.4 (13.7) | 47.3 (13.5) | 48.5 (13.3) |
| % Female | 57.1 | 57.7 | 57.5 |
| Cigarettes per day: M (SD) | 16.9 (10.4) | 17.2 (10.2) | 17.3 (10.0) |
| % Recruited each wave | |||
| Wave 1 | 56.4 | 43.2 | 30.8 |
| Wave 2 | 12.9 | 9.4 | 6.5 |
| Wave 3 | 30.8 | 20.9 | 14.3 |
| Wave 4 | NA | 26.5 | 16.3 |
| Wave 5 | NA | NA | 32.2 |
| % Country | |||
| Canada | 25.1 | 25.6 | 25.0 |
| USA | 21.7 | 23.5 | 22.7 |
| UK | 25.7 | 24.9 | 25.3 |
| Australia | 27.5 | 26.0 | 27.1 |
| % Made a quit attempt by following wave | 41.1 | 38.3 | 37.3 |
| % Quit >1 month (maintenance) among those who trieda | 24.6 | 25.7 | 25.3 |
Notes. NA = not applicable.
a
Excludes respondents quit for less than a month at follow-up (n = 83 at Wave 4; n = 88 at Wave 5; and n = 81 at Wave 6).