Results
ASH
The ASH Youth Survey was completed by 2513 youths, of whom 2469 (1286 female youths [52.1%]; mean [SD] age, 15.0 [2.3] years) were included in the analytical sample; the ASH Adult Survey was completed by 12 248 adults, of whom 12 046 (6412 women [53.2%]; mean [SD] age, 49.9 [17.4] years) were included in the analytical sample. Participant demographic characteristics are presented in eTables 3 and 4 in When testing for successful randomization, except for social grade among the adult sample (χ