Expanding Hybrid Studies for Implementation Research: Intervention, Implementation Strategy, and Context.

Area of Science:

• Implementation Science
• Health Services Research
• Study Design Methodology

Background:

• Hybrid effectiveness-implementation studies assess interventions and strategies, but context's role as an independent variable is often unclear.
• Existing frameworks incompletely specify the interplay between intervention, implementation strategy, and context.
• A more comprehensive typology is needed to advance implementation science.

Purpose of the Study:

• To expand the hybrid typology for effectiveness-implementation studies to incorporate intervention, implementation strategy, and context as independent variables.
• To propose a notation system (I, IS, C) for classifying hybrid study types.
• To detail specific two- and three-variable hybrid study designs.

Main Methods:

• Conceptual framework development building upon existing typologies (e.g., Curran et al.).
• Proposal of a systematic notation for primary and secondary independent variables.
• Detailed description of four two-variable hybrid types (I/is, IS/c, IS-C, C/is) and seven three-variable types.

Main Results:

• An expanded framework specifying nine two-variable and seven three-variable hybrid study types.
• A proposed notation system using 'I' for intervention, 'IS' for implementation strategy, and 'C' for context.
• Identification of existing studies that fit the proposed definitions.

Conclusions:

• The proposed expanded typology offers a more complete specification of hybrid study designs.
• Incorporating context as a key independent variable is essential for advancing implementation science.
• Future research should measure context's impact on implementation to bridge the evidence-practice gap.