Table 4 Stepwise controlled models of the association between educational track and smoking (more than once a month vs. once a month or less)

 High

1.00

1.00

1.00

1.00

 Middle

5.92 (2.39–14.68)

4.00 (1.54–10.37)

3.22 (1.20–8.65)

3.02 (1.08–8.42)

 Low

5.74 (2.31–14.29)

5.27 (2.09–13.30)

3.42 (1.18–9.92)

3.40 (1.11–10.37)

 Male

1.00

1.00

1.00

1.00

 Female

0.76 (0.38–1.51)

0.81 (0.39–1.65)

0.86 (0.42–1.79)

0.82 (0.39–1.74)

Age

1.64 (1.14–2.35)

1.64 (1.14–2.37)

1.62 (1.12–2.34)

1.74 (1.19–2.55)

Social disadvantage

0.69 (0.50–0.95)

0.72 (0.52–1.00)

0.71 (0.51–1.00)

0.67 (0.47–0.95)

Self-control^a

0.55 (0.37–0.82)

0.53 (0.36–0.80)

0.52 (0.35–0.79)

Cognitive ability^a

0.72 (0.57–1.08)

0.70 (0.46–1.08)

Reaction time^b

1.40 (0.94–2.11)

Memory span Forwards^a

1.05 (0.71–1.56)

Memory span Backwards^a

1.33 (0.92–1.94)

Model fit AIC, p-value^c

212.6, 0.002

205.1, 0.002

204.5, 0.106

206.8, 0.219