We present results of models that included a control variable for study sample because of different study enrollment criteria. There was overlap between birth cohort and study (e.g., some studies had younger or older participants), and to test whether controlling for study removed variance related to birth cohort, we conducted sensitivity analyses uncontrolled for study. Results (not shown) were substantively the same. Additionally, the cohort exposure group was changed from birth year to birth year plus 10 to mimic age of first tobacco exposure. Results (not shown) were consistent with the birth cohort findings.
