Factors associated with social exchange among past-month smokers, grades 8–10*
| Variable | Category | LS Mean | p Value |
|---|---|---|---|
| *Using mixed model multiple regression analysis. | |||
| LS Mean, adjusted least squares mean social exchange score. | |||
| Grade | 8 | 18.41 | 0.0165 |
| 9 | 18.89 | ||
| 10 | 18.31 | ||
| Sibling smokes | Yes | 19.20 | <0.0001 |
| No | 17.96 | ||
| Best friend smokes | Yes | 19.24 | <0.0001 |
| No | 18.84 | ||
| Most friends smoke | Yes | 19.24 | <0.0001 |
| No | 16.43 | ||
| Usually buy own cigarettes | Yes | 20.18 | <0.0001 |
| No | 17.38 | ||
| Variable | β Coefficient | p Value | |
| Number of cigarettes/week (A) | 0.03005 | <0.0001 | |
| Year of smoking initiation | −0.2754 | <0.0001 | |
| Teen norms against smoking scale (B) | −0.01594 | 0.0043 | |
| Parent smoking influences scale | 0.1161 | <0.0001 | |
| Ever commercial source scale | 2.0733 | <0.0001 | |
| Interaction of A and B | 0.00036 | 0.0014 | |