Table 3

Unadjusted relative risk ratios for changes in susceptibility and smoking status in relation to explanatory variables 2012–2013

Among non-susceptible never-smokers at baselineAmong susceptible never-smokers at baseline
RRR of becoming susceptibleRRR of becoming an ever-smokerRRR of becoming non-susceptibleRRR of becoming an ever-smoker
Estimate99% CIp ValueEstimate99% CIp ValueEstimate99% CIp ValueEstimate99% CIp Value
Smoking in the main family home
 Not allowed1.001.00  1.00 1.00 
 Allowed2.001.11 to 3.600.0024.111.05 to 16.140.0081.180.20 to 6.840.8131.850.68 to 4.990.111
Number of friends who smoke
 None1.001.00  1.00 1.00 
 One or two1.510.73 to 3.110.1441.940.89 to 4.260.0290.750.17 to 3.300.6232.480.36 to 17.080.225
 Three or more1.670.65 to 4.260.1616.381.63 to 25.04<0.0010.570.15 to 2.150.2783.090.43 to 22.110.140
 Not sure1.140.60 to 2.140.6042.551.05 to 6.210.0070.570.24 to 1.350.0902.430.37 to 16.010.226
Self-perceived academic performance
 Excellent or good1.001.00 1.00 1.00 
 Average or below average1.030.48 to 2.220.9232.111.03 to 4.330.0071.400.87 to 2.270.0701.400.68 to 2.890.230
Rebelliousness
 Low1.001.001.001.00
 High1.890.77 to 4.650.0682.820.99 to 7.990.0111.090.59 to 2.040.7101.480.64 to 3.470.230
Noticing point-of-sale displays in large shops
 Sometimes or less1.001.00p1.001.00
 Most or every time0.790.52 to 1.180.1281.010.43 to 2.380.9660.520.33 to 0.81<0.0011.850.72 to 4.720.093
Frequency of visiting large shops
 Less than 2 or 3 times a week1.001.001.001.00
 At least 2 or 3 times a week0.560.33 to 0.960.0050.410.17 to 0.970.0080.740.39 to 1.400.2260.540.32 to 0.930.003
Noticing point-of-sale displays in small shops
 Sometimes or less1.001.001.001.00
 Most or every time0.800.42 to 1.540.3830.890.36 to 2.200.7360.790.25 to 2.520.6031.380.37 to 5.120.532
Frequency of visiting small shops
 Less than 2 or 3 times a week1.001.001.001.00
 At least 2 or 3 times a week1.010.61 to 1.680.9520.360.11 to 1.170.0250.900.27 to 3.030.8290.230.09 to 0.55<0.001
Number of brands recognised
 None1.001.001.001.00
 1–51.200.69 to 2.090.4061.140.34 to 3.790.7810.400.15 to 1.070.0161.070.38 to 3.040.859
 More than 51.811.29 to 2.54<0.0012.020.50 to 8.140.1950.530.12 to 2.250.2561.830.59 to 5.690.170
  • Sex, age, quintiles of Index of Multiple Deprivation, parental smoking and sibling smoking not presented as these were not significant predictors for any of the outcome variables.

  • RRR, relative risk ratios.