Descriptive statistics and bivariate polychoric correlations for educational and substance use variables are given in Table 1. Across age, school performance and education variables were strongly positively associated, with polychoric correlations ranging from .6 to .8 (p<.001). Associations between alcohol use variables were more variable, with polychoric correlations mostly in the range of .2 (p<.01) to .5 (p<.001). Smoking variables were consistently positively correlated, with polychoric correlations between .4 and .8 (p<.001). In most cases, educational achievement was inversely associated with alcohol use and smoking, with polychoric correlations typically ranging between −.2 and −.4 (p<.001). These correlations were stronger for smoking behaviors than for any drinking or drinking to intoxication.
