Table 3

An example of the full logistic regression model used to compare the proportion of crashes where the response variable was one of the driving restrictions (night-time curfew in this example) and the main explanatory variable was type of licence (in this example pre-GDL drivers were compared with restricted licence drivers)

EstimatesdfEstimateSEχ2p Value>χ2Odds ratio95% confidence interval
Intercept1 1.8091.504 1.45 0.229
Licence type
    Pre-GDL: restricted1−0.420.14 9.13 0.0030.660.50 to 0.86
Driver age (years)
    19 : 151 0.7860.12015.5<0.00012.201.50 to 3.29
    19 : 161 0.6060.12423.7<0.00011.831.44 to 2.34
    19 : 171 0.2210.106 4.34 0.0371.251.01 to 1.54
    19 : 181 0.0410.098 0.18 0.6761.040.86 to 1.26
Gender
    Female: male1 0.4630.09523.55<0.00011.591.32 to 1.92
Year of crash1−0.0130.016 0.65 0.4220.990.96 to 1.02