on two related outcome measures (e.g., AP and HED) may be more insightful than those from an isolated single outcome when assessing clinical significance at the individual level or global cost-effectiveness. Recent advances in longitudinal research methodology (see Foster & Kalil, 2008) provide attractive analytic options for evidence-based intervention research. The refined focus on subgroup analysis utilized in the present study may be beneficial in the future for tailoring necessary intervention components to those who need them the most.
