Fig. 1.

Two-stage review design following the ‘best fit’ framework synthesis approach, based on Carroll et al. [13]. Legend: The review applies a two-stage process. In the first stage, we will review existing frameworks, models, concepts and theories (stage 1—framework review). Concepts for external implementation context will be synthesised in an a priori meta-framework. In the second stage, we will test and refine the a priori meta-framework by analysing evidence from empirical studies that focus on the implementation of health and social care interventions into practice within or across countries (stage 2—empirical study review). The concepts derived from both reviews will be synthesised into a final framework