2.1. Study Design
A mixed method was used to conduct this study—semi-structured interviews were conducted to collect qualitative data, and questionnaires were employed to collect quantitative data. Participating families were randomly assigned to one of two interventions–a clinician-facilitated intervention (Family Talk) or a lecture-based intervention. Details of the randomized longitudinal study of the two family-based preventive interventions, including intervention allocation patterns and short-term intervention effects, have been reported previously [