Selected descriptive statistics for all adolescent predictors by quintiles of ND at age 42.

Note that for ordinal variables except quintiles of ND at age 16, descriptives are shown only for a single (collapsed) category, as indicated in the table. Bivariate associations were however estimated using the full range of each variable.ap value from χ2.bp value from Mantel-Haenszel test.cp value from Spearman's ρ.