Table 1.

Dimensions of scale-up and possible implementation research questions

Scaling-up dimensions informed by implementation research	Possible implementation research questions related to scaling-up
Attributes of the innovation or service	Appropriateness: How appropriate and effective is the intervention? How well does it fit with the context and actors? Fidelity: Did the attributes of the innovation remain the same as planned throughout the implementation process? How were they adapted over time?
Attributes of the target community and actors involved in scale-up	Acceptability: How acceptable is the intervention to key stakeholders? Intention to adopt: What are stakeholders intentions to adopt the intervention, and why is this the case? Coverage: Who is covered by the intervention? What are the attributes of those who are covered, and those who are not?
Context	Feasibility: Is it possible to implement the intervention in this context, given the resources available, the health systems structures, etc.?
Scaling-up strategy	Implementation cost: How much does it cost to deliver the intervention? Is this affordable? Could adaptations to design make the intervention more cost-effective? Sustainability: Is it possible to sustain the intervention once scaled up? What factors (intervention attributes, actors involved, context) contribute to or undermine sustainability?

Source: Adapted from Peters et al. [15]