Figure 1
A flowchart illustrating the key components of the Medical Research Council framework for evaluating complex interventions. The flowchart includes several interconnected boxes and arrows indicating the flow and relationships between different aspects. The top section is labeled 'Context' and includes factors that shape theories of how the intervention works, factors affecting implementation, and causal mechanisms within the context. The left section is labeled 'Description of intervention and its causal assumptions,' which leads to the 'Implementation' section. The 'Implementation' section details the implementation process, what is delivered, fidelity, dose, adaptations, and reach. This section connects to the 'Mechanisms of impact' section, which includes participant responses to the intervention, mediators, and unexpected pathways and consequences. The 'Mechanisms of impact' section leads to the 'Outcomes' section on the right.Key functions of process evaluation and relations among them by Moore et al. (2015)