Table 3

Zero inflated negative binomial estimates for cigarette consumption (negative binomial process)

VariableAllBoysGirls
95% CI95% CI95% CI
IRRP valueLowHighIRRP valueLowHighIRRP valueLowHigh
Visibility teacher smoking
 Daily1.070.170.971.171.15*0.041.011.310.990.910.881.12
 Most days1.120.260.921.371.340.080.961.850.990.940.841.17
 Half of the days1.090.260.941.271.060.650.831.351.100.310.911.33
 Less than half days1.010.930.871.171.100.440.871.380.930.410.791.10
 Never (reference category)
Friends smoke0.640.150.351.180.990.980.601.630.500.100.221.13
Mother smokes1.20***0.001.111.291.17**0.011.041.311.24***0.001.121.37
Father smokes1.09*0.041.011.181.130.051.001.281.040.400.951.15
School type (public)0.950.380.851.060.910.250.781.071.010.920.871.17
School Programme0.950.260.861.040.940.420.821.080.940.290.841.05
Male1.060.160.981.16
Age 14 (reference category)
Age 151.34*0.011.061.701.160.460.781.731.50**0.001.171.93
Age 161.83***0.001.452.301.56*0.031.052.302.05***0.001.622.60
Age 171.83***0.001.462.301.63*0.011.122.382.03***0.001.602.58
Age 182.08***0.001.622.681.85**0.001.232.792.23***0.001.672.97
Immigrant0.950.530.801.120.980.820.781.220.950.650.751.20
Income1.00***0.001.001.011.00***0.001.001.011.00***0.001.001.01
Working mother0.960.320.891.040.87*0.020.770.981.040.450.941.14
Working father1.030.640.921.141.060.510.901.251.000.970.881.14
Retired mother0.960.800.711.310.58*0.020.370.911.51*0.011.102.08
Retired father1.290.060.991.691.470.070.972.231.130.370.861.49
Bad relations mother1.060.540.891.261.050.750.781.401.100.300.921.32
Bad relations father1.130.080.991.301.080.520.861.361.140.130.961.36
Intercept3.96***0.002.087.543.09**0.001.625.884.52***0.001.9610.45
N° Observations19 38295769626
N° of zeros16 23383187915
  • Sampling weights have been taken into account with the ‘ svyset ’ and ‘ svy’ commands.

  • *P<0.05; **P<0.01; ***P<0.001.

  • IRR, incidence rate ratio.