Table 2

Odds ratios of linear and quadratic models for smoking attitudes among students in England and Scotland (trying smoking is ‘OK’, from 1999 to 2015) and England only (smoking weekly is ‘OK’, from 2003 to 2014)

Trying smoking is OK* (don’t know=not OK)Smoking weekly is OK† (don’t know=not OK)
LinearP valueQuadraticP valueLinearP valueQuadraticP value
Whole sample
(n=165 199; 35 890)
Year0.91 (0.91 to 0.92)<0.0010.87 (0.85 to 0.89)<0.0010.91 (0.90 to 0.92)<0.0010.72 (0.65 to 0.81)<0.001
Year2 1.00 (1.00 to 1.00)<0.0011.01 (1.01 to 1.02)<0.001
Level1.03 (0.97 to 1.10)0.3301.05 (0.98 to 1.12)0.1431.15 (1.00 to 1.32)0.0451.10 (0.96 to 1.27)0.152
Post-slope0.92 (0.90 to 0.93)<0.0010.88 (0.86 to 0.90)<0.0010.95 (0.90 to 1.00)0.0320.82 (0.75 to 0.89)<0.001
Male only subgroup
(n=82 270; 18 042)
Year0.92 (0.91 to 0.93)<0.0010.84 (0.81 to 0.87)<0.0010.92 (0.91 to 0.94)<0.0010.67 (0.57 to 0.79)<0.001
Year2 1.01 (1.00 to 1.01)<0.0011.02 (1.01 to 1.03)<0.001
Level1.08 (0.99 to 1.18)0.0901.11 (1.01 to 1.22)0.0241.33 (1.10 to 1.62)0.0041.27 (1.04 to 1.54)0.020
Post-slope0.91 (0.89 to 0.93)<0.0010.84 (0.81 to 0.88)<0.0010.88 (0.82 to 0.94)<0.0010.71 (0.62 to 0.81)<0.001
Female only subgroup
(n=82 929; 17 848)
Year0.90 (0.90 to 0.91)<0.0010.89 (0.86 to 0.93)<0.0010.90 (0.88 to 0.91)<0.0010.77 (0.66 to 0.91)0.001
Year2 1.00 (1.00 to 1.00)0.4921.01 (1.00 to 1.02)0.067
Level0.98 (0.90 to 1.07)0.7180.99 (0.90 to 1.08)0.7891.02 (0.84 to 1.22)0.8660.99 (0.82 to 1.19)0.917
Post-slope0.93 (0.91 to 0.95)<0.0010.92 (0.88 to 0.95)<0.0011.01 (0.95 to 1.08)0.7200.92 (0.81 to 1.04)0.180
13 year olds only
(n=85 713; 18 721)
Year0.90 (0.89 to 0.91)<0.0010.89 (0.86 to 0.92)<0.0010.90 (0.89 to 0.92)<0.0010.78 (0.65 to 0.94)0.007
Year2 1.00 (1.00 to 1.00)0.4591.01 (1.00 to 1.02)0.107
Level0.95 (0.86 to 1.05)0.3210.95 (0.87 to 1.05)0.3491.22 (0.97 to 1.53)0.0861.19 (0.94 to 1.49)0.145
Post-slope0.94 (0.92 to 0.97)<0.0010.93 (0.90 to 0.97)<0.0010.93 (0.85 to 1.01)0.0920.84 (0.73 to 0.98)0.022
15 year olds only
(n=79 486; 17 169)
Year0.93 (0.92 to 0.94)<0.0010.86 (0.83 to 0.89)<0.0010.91 (0.90 to 0.93)<0.0010.70 (0.60 to 0.80)<0.001
Year2 1.00 (1.00 to 1.01)<0.0011.01 (1.01 to 1.02)<0.001
Level1.09 (1.01 to 1.19)0.0341.13 (1.04 to 1.23)0.0061.11 (0.94 to 1.32)0.2181.06 (0.90 to 1.26)0.473
Post-slope0.89 (0.87 to 0.91)<0.0010.83 (0.80 to 0.86)<0.0010.96 (0.90 to 1.02)0.1440.80 (0.71 to 0.89)<0.001
  • *Available for England and Scotland only.

  • †Available for England only.