UCSF trials: comparisons of baseline characteristics
| Variable | Trial 1 N=149 | Trial 2 N=199 | Trial 3 N=219 | Trial 4 N=160 | Significance* | Effect size* | Significance† | Effect size† |
|---|---|---|---|---|---|---|---|---|
| M (SD) | M (SD) | M (SD) | M (SD) | |||||
| Cigarettes per day | 24.9 (10.8) | 22.5 (9.8) | 21.4 (9.0) | 19.2 (7.2) | F(3, 723)=10.4, p<0.001 | 0.04es | F(3, 712)=9.63, p<0.001 | 0.04es |
| Nicotine dependence‡ | 6.4 (1.9) | 5.5 (2.1) | 4.8 (2.2) | 4.6 (2.0) | F(3, 709)=24.0, p<0.001 | 0.09es | F(3, 699)=22.67, p<0.001 | 0.09es |
| Current depressive symptoms§ | 5.1 (5.1) | 8.9 (7.0) | 8.1 (7.2) | 8.4 (7.3) | F(3, 716)=9.7, p<0.001 | 0.04es | F(3, 706)=9.65, p<0.001 | 0.04es |
| Age | 40.6 (9.2) | 40.7 (9.6) | 39.4 (11.3) | 38.6 (10.0) | F(3, 719)=1.8, p=0.15 | 0.01es | ||
| Body mass index | 24.4 (3.8) | 24.9 (3.6) | 24.9 (4.5) | – | F(2, 526)=0.8, p=0.46 | 0.00 | ||
| % Female | 52.3 | 55.3 | 44.3 | 41.3 | χ2(3)=9.5 p=0.02 | 0.11v | ||
| % Partnered | 38.3 | 41.6 | 33.8 | 46.5 | χ2(3)=6.7 p=0.08 | 0.10v | ||
| % Minority | 12.1 | 12.2 | 17.8 | 22.5 | χ2(3)=9.3 p=0.03 | 0.11v | ||
| % College degree | 59.7 | 53.3 | 54.6 | – | χ2(2)=1.5 p=0.46 | 0.05v |
*0.01 small, 0.06 medium and 0.14 large; Partial η2: 0.04 recommended minimum effect size; Cramer's V: 0.2 recommended minimum effect size.
†Significance after controlling for sex, age and minority status.
‡Nicotine dependence was self-reported using the Fagerström Test for Cigarette Dependence34
§Current depressive symptoms were self-reported using the Beck Depression Inventory (BDI-II).
¶Partnered refers to participants who reported that they had a live-in partner.
es, η2; v, Cramer's V.