Finally, a process evaluation nested inside the trial will be conducted in order to assess
fidelity and
quality of implementation, to clarify causal mechanisms and to identify contextual
factors associated with variation in outcomes.179
Critical features of MST include: (a) integration of empirically based treatment approaches to address a comprehensive range of risk
factors across family, peer, school, and community contexts; (b) promotion of behavior change in the youth's natural environment, with the overriding goal of empowering caregivers; and (c) rigorous
quality assurance mechanisms that focus on achieving outcomes through maintaining treatment
fidelity and developing strategies to overcome barriers to behavior change.