A method for defining the CORE of a psychosocial intervention to guide adaptation in practice: Reciprocal imitation teaching as a case example.

LAY ABSTRACT: Interventions that support social communication include several "components," or parts (e.g. strategies for working with children and families, targeting specific skills). Some of these components may be essential for the intervention to work, while others may be recommended or viewed as helpful but not necessary for the intervention to work. "Recommended" components are often described as "adaptable" because they can be changed to improve fit in different settings where interventions are offered or with different individuals. We need to understand which parts of an intervention are essential (and which are adaptable) when translating interventions from research to community settings, but it is challenging to do this before studying an intervention in the community. This article presents the CORE (COmponents & Rationales for Effectiveness) Fidelity Method-a new method for defining the essential components of evidence-based interventions-and applies it to a case example of Reciprocal Imitation Teaching, an intervention that parents are taught to deliver with their young children with social communication delays. The CORE Fidelity Method involves three steps: (1) gathering information from multiple sources; (2) integrating information from previous research and theory; and (3) drafting a CORE model for ongoing use. The benefits of using the CORE Fidelity Method may include: (1) improving consistency in intervention and research materials to help all providers emphasize the most important skills or strategies; (2) clarifying which parts of the intervention can be adapted; and (3) supporting future research that evaluates which intervention components work and how they work.