Background: Entering the realm of implementation and scale-up science is a dynamic, important, worthwhile venture. But there are challenges. Amidst a wide array of choices, researchers must identify appropriate frameworks to guide their implementation or scale-up study. What implementation strategies (i.e., methods to enhance adoption, implementation, and sustainability of an intervention) effectively support scaling-up the intervention? What indicators (determinants and outcomes) are best suited to demonstrate effectiveness of the scale-up process? What are core functions and what are the mechanisms through which they operate?

More and more scientists in physical activity (PA) and behavioural (nutrition) seek to understand the science of implementation and scale up. Advancing this science in our disciplines is predicated upon us addressing the ​questions we pose above, adopting more deliberate implementation and scale-up science approaches and increased efforts to develop a common language and adaptable measures and tools.

In this presentation we share results of a five-round Delphi process, conducted with an international group of PA and nutrition implementation and scale-up scientists. We will present implementation and scale-up frameworks and a minimum data set ​of indicators they deemed most relevant to those in PA and nutrition research. Finally, we will discuss when, where and how implementation strategies, implementation determinants and outcomes can be incorporated into your research. We animate our presentation with two scale-up case studies that span 5-10 years (Action Schools! BC and Choose to Move) to illustrate how implementation and scale-up science can be applied and how it evolves over the lifetime of a project. We close with a brief synopsis of key research and measurement gaps that need to be addressed to advance implementation and scale-up science in PA and nutrition research.

Purpose: Most often research trials are conducted under controlled conditions. Studies are designed to test interventions that, should they be delivered at scale in the real world, would require substantial adaptation. In this presentation we seek to describe the frequency and type of adaptations that facilitate scale-up of behavioural nutrition and physical activity interventions; we characterise the impacts of adaptations on intervention effectiveness.

Methods: We will advance the theory and practice of adaptation for scale-up in implementation science. To do so we call upon an array of real-world implementation and scale-up studies to animate the science. Approaches include qualitative studies of end-users, surveys of researchers, and systematic reviews that examine the impact of adaptations on the effects of scaled-up behavioural and nutrition interventions. 

Results: Fewer than one third of interventions are not adapted prior to implementation at scale. Most commonly studies are adapted by removing or adding intervention components, modifying the intervention and mode of delivery to the suit the target audience and the delivery context. When implemented at scale, the effects of interventions attenuate. Effects at scale are typically no more than 75% of that reported in ‘pre-scale up’ evaluations. Researchers of scaled-up interventions had mixed views about the impact of adaptations on the effect of interventions. Some believed that adaptations would strengthen the impact; others believed that adaptation would dilute effectiveness at scale. At present, relationships between specific types of adaptations and effects of scaled-up interventions is unclear (systematic reviews).

Conclusion: Adaptation is a common, and likely necessary part of the scale-up process for behavioural nutrition and physical activity interventions. To realise both benefits and challenges of delivering interventions at scale, we need to better understand the process, evaluation and impact of adaptation.

Purpose: Choosing an appropriate evaluation approach and executing it effectively is central to generating credible evidence of the effectiveness and sustainability of scaled up health promoting interventions. 

Methods: in this presentation we consider the utility of different evaluation approaches, challenges and pragmatic approaches to evaluate scaled up population health interventions. 

Results. Selecting the appropriate evaluation approach requires researchers to consider: implementation stage; intervention setting; availability of program monitoring data; budget for and cost of the evaluation; feasibility of conducting the study design and acceptability of the design to stakeholders and participants. Experimental designs offer the most rigorous way of determining whether a cause-effect relationship exists between an intervention and an outcome. However, it is likely not practical (pragmatic) or appropriate to evaluate scaled up population-based interventions using this approach. Specifically, when evaluating scaled up interventions the focus shifts from an emphasis on outcomes to better understanding intervention implementation processes and from a research frame to a focus on measuring implementation at a systems level.  

Conclusion: To effectively conduct a pragmatic evaluation during scale-up of health promoting interventions, the approach must balance rigour, practice based knowledge and producing timely data that can be systematically integrated into decision making processes.