Table 2. RE-AIM domains

RE-AIM domain	Working definition	Application to digital technology
Reach	The absolute number, proportion and representativeness of individuals who have access to and are willing to participate in a given intervention (also known as coverage).	Among the target audience of the technology, *who* actually begins using (patient-facing technology), is registered to use (health- system facing technology) or receives actionable information using the technology (patient or health system-facing technology)?
Effectiveness	The impact of an intervention on important individual-level outcomes, including potential negative effects, quality of life and economic outcomes, under real-world conditions (as opposed to efficacy, which relates to benefits and harms associated with use of the technology under optimal conditions)	What are the important benefits expected to be achieved by deploying the technology and what are the potential negative outcomes? What factors contributed to these results?
Adoption	The absolute number, proportion and representativeness of settings and intervention agents (i.e., those who are responsible for delivering the intervention), who have access to and are willing to implement the intervention. In contrast to Reach, Adoption focuses on the setting/organization uptake of an intervention, beyond individual access to it.	*Where* or in *which settings* is the technology being deployed, and *who* within these settings is adopting it? *What* organizational-level factors impact this adoption?
Implementation - Fidelity - Acceptability - Consistency - Adaptation - Cost	Implementation can apply to both the individual user and the setting level. It refers to how closely the implementation of an intervention matches its original plan or design (known as fidelity), such as the delivery or use of each component as intended and the time and costs of the intervention. Implementation can also include the degree to which individuals or implementing agents perceive the intervention to be agreeable or appropriate (acceptability), the variation in delivery or use of the intervention across settings (consistency), changes made to the intervention or how it is delivered (adaption) and, incremental/marginal cost of delivering or using the intervention (cost)	What is the perceived acceptability of the technology? *How* consistently is the technology delivered and used as intended? *How* is it adapted? *How* much does it cost?
Maintenance	The extent to which an intervention continues to be used and/or is integrated and institutionalized after initial implementation. Maintenance can also apply at the individual level and is defined as the long-term effects of an intervention on outcomes six or more months after contact with the intervention.	*When* will the intervention become operational; how long will it be sustained (setting level); and how long will the results be sustained (individual level)?

^a Definitions applied for the purposes of this document have been adapted from Glasgow et al. from the RE-AIM organization.