where β1 is the intercept, β2 is the slope for the linear time term, β3 is the effect of life events at the prior assessment (at time j-1) on subsequent adolescent externalizing (at time j), β4 is the effect of sex on externalizing, β5 is the effect of parental externalizing problems on adolescent externalizing, β6 is the effect of number of parental externalizing reporters on adolescent externalizing, b1 is the random intercept allowing for individual variation around the mean (β1), b2 is the random intercept allowing for individual variation around the slope (β2), and β1i and β2i denote the participant-specific intercepts and slopes. We note that we used parental externalizing to predict intercepts but not slopes of adolescent externalizing because we anticipated that parental externalizing would predict initial levels of adolescent externalizing, but not necessarily changes in externalizing behavior across time. This was confirmed in preliminary analyses.
