Table 2

Multilevel mixed effects linear regressions for current smoking frequency in waves 2, 3 and 4 with baseline covariates

Wave 2Wave 3Wave 4
Estimate95% CIp ValueEstimate95% CIp ValueEstimateEstimate 95% CIp Value
Intercept1.201.08 to 1.320.0001.241.08 to 1.400.0001.401.20 to 1.600.000
IG-no participation and control group0.01−0.09 to 0.110.8640.06−0.06 to 0.180.3270.07−0.11 to 0.250.399
Occasional use0.580.40 to 0.760.0000.290.04 to 0.540.0220.550.26 to 0.840.000
Regular use2.332.11 to 2.550.0002.281.95 to 2.610.0002.051.66 to 2.440.000
Age0.080.04 to 0.120.0000.130.07 to 0.190.0000.100.02 to 0.180.005
Female gender0.080.02 to 0.140.0060.110.03 to 0.190.0050.220.12 to 0.320.000
Sensation Seeking0.210.11 to 0.310.0000.310.19 to 0.430.0000.460.30 to 0.620.000
Parenting−0.05−0.11 to 0.010.1260.02−0.06 to 0.100.691−0.02−0.12 to 0.080.646
Parent smoking0.060.00 to 0.120.0570.120.04 to 0.200.0040.150.05 to 0.250.002
Peer smoking0.160.10 to 0.220.0000.230.15 to 0.310.0000.240.14 to 0.340.000
Sibling smoking0.060.00 to 0.120.079−0.01−0.09 to 0.070.8290.160.06 to 0.260.004
Student-rated class climate0.00−0.06 to 0.060.9430.02−0.08 to 0.120.617−0.01−0.13 to 0.110.807
Student smoking class level0.08−0.02 to 0.180.1210.160.02 to 0.300.0200.06−0.12 to 0.240.504
Teacher-rated class climate−0.04−0.18 to 0.100.5560.10−0.06 to 0.260.2170.01−0.23 to 0.250.926
School type−0.11−0.23 to 0.010.058−0.08−0.22 to 0.060.246−0.18−0.36 to 0.000.057
IG-no participation and CG×occasional use0.360.14 to 0.580.0010.550.26 to 0.840.0000.16−0.19 to 0.510.386
IG-no participation and CG×regular use0.16−0.08 to 0.400.183−0.28−0.63 to 0.070.136−0.12−0.55 to 0.310.596
NICCNICCNICC
Students30130.7925050.8123450.82
Classes2050.121860.081820.09
Schools830.09810.11790.09
  • CG, control group; IG, intervention group; ICC, intraclass correlation.