person for each year of life. For cases positive for ODD, CD, MDD, or Trauma, a time-dependent variable was computed as 0 (absent) for each year up to the age of onset of the risk factor, and then 1 (present) from that year onward. Time invariant binary endorsements were used for (a) early age behaviors (e.g., under the age of 7 or 13), (b) when data were lifetime endorsements (e.g., have you ever had event X), or (c) when data reflected current status (e.g., family income).
