Although the positive youth development (PYD) model initially assumed inverse links between indicators of PYD and of risk/problem behaviors, empirical work in adolescence has suggested that more complex associations exist between trajectories of the two domains of functioning. To clarify the PYD model, this study assessed intraindividual change in…

The study of adolescent development rests on methodologically appropriate collection and interpretation of longitudinal data. While all longitudinal studies of adolescent development involve missing data, the methods to treat missingness that have been recommended most often focus on missing data from cross-sectional studies. The problems of…