An initial typology of approaches used by policy and practice agencies to achieve sustained implementation of interventions to improve health.

Background: Scientific investigation of how to sustain the implementation of evidence-based interventions (EBI) is emerging. Sustaining the implementation of EBIs helps ensure their effects on improving health endure. External policy or practice agencies, such as government health departments, are often tasked with supporting individual organisations with sustaining their delivery of EBIs, for example, through financing, training or the provision of other supports. However, to our knowledge, the approaches taken by policy and practice agencies to support the sustainment of EBIs have not been consolidated, categorised and described as a typology. Main body: To improve conceptual clarity and support both research and practice, we developed an initial working typology of the practical approaches to sustain implementation of EBIs (i.e. sustainment) in order to improve long term health from the perspective of these agencies. The working typology includes three broad approaches. The first, termed ‘Self-Sustainment’, is when implementation of the EBI by an organisation (e.g. hospital, clinic, school) is expected to continue (sustain) in the absence of external (agency) support. The second, termed ‘Static Sustainment Support’, involves the provision of pre-defined external (agency) support to assist organisations to continue implementation of an EBI. The final approach is termed ‘Dynamic Sustainment Support’, whereby support provided by an external agency is dynamic (continues to be adapted) overtime to assist organisations continue implementation of an intervention which may itself also evolve. Conclusions: We describe the contexts and circumstances where each may be most appropriate in achieving sustained implementation and discuss their research and practice implications.