Table 2

Unadjusted and adjusted ORs (95% CI) for the association between teacher-reported practices and policy content with lifetime cannabis use, cannabis use in the last 30 days, cannabis use daily in the last 30 days, lifetime mephedrone and NPS use

Lifetime cannabis useCannabis last 30 daysCannabis dailyLifetime mephedrone useLifetime NPS use
NullModel 1Model 2NullModel 1Model 2NullModel 1Model 2NullModel 1Model 2NullModel 1Model 2
Teacher reported (n=18 939)
Student involvement in policy development
Student council
1.24
0.89 to 1.73
1.25 0.85 to 1.841.38
0.82 to 2.32
1.06 0.67 to 1.561.31 0.92 to 1.87
Other consultation1.42
0.94 to 2.14
1.35
0.84 to 2.17
1.46
0.79 to 2.70
1.00 0.62 to 1.601.16 0.75 to 1.79
Use isolation0.98
0.67 to 1.43
1.08
0.70 to 1.67
1.12
0.64 to 1.98
1.96 1.17 to 3.281.03
0.69 to 1.55
ICC0.090.060.060.100.070.060.110.040.030.070.030.020.060.020.02
BIC7192.836174.396200.64593.394143.344170.801666.771570.191597.592347.792247.802270.283008.632814.192841.51
AIC7177.135970.315972.984577.703939.273943.181651.081366.121369.972332.092043.722042.662992.932610.112613.89
Policy content (n=9006)
Condemns0.77
0.45 to 1.31
0.98
0.54 to 1.77
1.18
0.67 to 2.06
1.05 0.65 to 1.721.68 1.06 to 2.66
ICC0.130.090.090.150.090.090.11<0.01<0.010.140.050.030.110.030.01
BIC4061.793452.203460.372461.902264.912274.01968.85944.59953.371292.081318.971328.031491.931454.511459.33
AIC4047.583253.243254.312447.692065.962067.95954.64752.74754.411277.871120.011121.971477.721255.551253.27
  • Reference categories for teacher-reported variables: no involvement of students in policy development; no use of isolation.

  • Reference categories for policy content variables: not condemning drug use. Model 1 adjusts for compositional variables: gender, year group, ethnicity, family structure, Family Affluence Scale, Free School Meal Entitlement and Welsh Index of Multiple Deprivation. Model 2 adjusts for school context variables: Involvement of students in policy development, use of isolation and condemnation of drugs.

  • AIC, Akaike information criterion; BIC, Bayesian information criterion; ICC, interclass correlation coefficient; NPS, novel psychoactive substances.