MIXED METHODS IN THE INTERVENTION PIPELINE
Mixed methods may be valuable throughout the pipeline—in the development of the intervention, during the evaluation of the intervention, and after the completion of the follow-up and assessment of outcomes. Typically, quantitative methods are used to assess intervention outcomes (shown in the upper right of Figure 11.2, adapted from Sandelowski, 1996), but qualitative methods may be introduced before, during, and after a trial (lower half of Figure 11.2). Qualitative approaches are most frequently used to develop an instrument, to understand strategies for successful recruitment, to find areas for intervention adaptation, to understand the processes of an intervention, to evaluate fidelity and other implementation factors, to explain outcomes, to provide feedback to improve intervention, and to understand mediators and moderators. As discussed in Chapter 16, qualitative methods are also sometimes used to gather information on the clinical significance of an intervention.
Traditional efficacy and effectiveness clinical trials focus on improving individual-level clinical and functional outcomes. For example, the National Institute of Mental Health (NIMH) is leading efforts to move toward an “experimental medicine approach” that generates knowledge about “mechanisms” underlying a disorder or a service use pattern (see Dr. Insel’s overview at http://www.nimh.nih .gov/about/director/2014/a-new-approach-to-clinical-trials.shtml). An emphasis is on understanding mechanisms and designing studies in such a way that even if an intervention has minimal effects, it will be possible to inform future improvements or modifications to the intervention (O’Cathain, Murphy, & Nicholl, 2007). Mixed methods are essential to achieving these objectives as it is no longer tenable for an investigator to answer only the question: Does this work? The investigator must also be prepared to address the questions: Why didn’t this work? Why didn’t this
Figure 11.2 The role and timing of using quantitative and qualitative approaches in randomized clinical trials.
Source: Adapted from Sandelowski (1996).
work for this group? Why didn’t this intervention reach the people for whom it was intended?
Mixed methods have the potential to discover, explain, or (dis)confirm mediators or moderators not traditionally identified through quantitative methods. Though quantitative methods in randomized controlled trials (RCTs) have been regarded as the gold standard for efficacy and effectiveness research, active integration of qualitative methods in behavioral intervention research facilitates the identification of complex procedural, contextual, and interpersonal factors underlying efficacy or effectiveness of interventions (Neuman, 2006). The emic, or insider’s perspective of cultural, interpersonal, and environmental contexts, provides a more complete understanding of the processes that determine success or failure of an intervention. Evidence-based practices that are appropriate for diverse groups and contexts in which the intervention will be deployed are more likely to be integrated into complex and evolving health systems.