Table 1 Key terms and definitions

Implementation strategies

The approaches and methods used to adopt, implement, and sustain EBIs [19].

Contextual factors

The global, national, MOH, and community/family/individual level factors which influence the success and failure of the implementation and effectiveness of the EBI [20]. These can also influence U5M rates more broadly. They can be addressed if a barrier, leveraged if a facilitator, inform implementation strategy choice or adaptation, or be acknowledged representing a factor not able to be addressed or adapted to through a strategy.

Implementation outcomes^a

The results of the implementation of the EBIs which represent “how well” implementation strategies were executed as well as the interaction between the strategies and contextual factors.

Appropriateness

The perceived fit of the intervention (as originally conceptualized and as implemented) to address a particular cause of death or for a specific setting.

Acceptability

The perception of stakeholders that an EBI is agreeable and is typically based on qualitative or user experience and attitudes^b and could include satisfaction with the type of services [19].

Coverage

The geographic or population spread of an EBI.

Cost

The incremental cost of the implementation of the intervention.

Effectiveness

The evidence of change in the targeted cause of disease and death.

Equity

The coverage or reach of EBIs among different subpopulations defined by factors such as wealth, gender, and geography.

Feasibility

The practicability of an EBI and the extent to which an intervention (as originally conceptualized and as implemented or as adapted) can be or has been successfully implemented, used, or carried out within a given setting.

Fidelity

Fidelity to the implementation: the degree to which an intervention was implemented as it was prescribed in the original plan or as it was intended by the program developers (before implementation and after adaptation).

Fidelity to the EBI: the degree to which the intervention was delivered as defined by guidelines and standards of care.

Reach

The extent to which an EBI reached everyone intended (see also equity).

Sustainability

The extent to which a newly implemented treatment is maintained or institutionalized within the ongoing and stable operations of a service setting. This measures if evidence of sustainability was seen, such as coverage rates maintained, or strategies implemented to support sustainment.