How is health equity considered in scale-up guidance? A scoping review of process models for scaling public health innovations

Scale-up guidance is valuable to guiding efforts to increase the reach and impact of public health innovations. Health equity, that is, 'the absence of systematic disparities in health between groups' is often a motivator for scale-up though it is unclear how 'equity' is considered within existing scale-up guidance. This scoping review aimed to identify the equity considerations articulated within existing scale-up models. Five databases and grey literature were systematically searched. Articles were included if they explicitly developed a model/framework to guide the process of scaling-up public health innovations. Search results were screened, and content analysis was undertaken. Of the 29 scale-up models identified, 24 included mention of equity terms or equity-related characteristics, however there was variation in how equity was conceptualized and the extent to which it was incorporated. Seven domains were developed to describe how equity was considered: (1) Equity acknowledged in the supporting text as an important factor when scaling-up; (2) Equity positioned as a guiding principle or cross-cutting theme; (3) Equity considered in scalable innovation design or intended population; (4) Equity incorporated into scale-up planning and strategy development; (5) Equity assessed within context and environment assessments; (6) Equity factored into resource allocation and workforce planning; (7) Equity considered in stakeholder engagement. There was considerable variation in how equity was considered which offers opportunities for enhancements. Existing and future scale-up models can be strengthened by applying a more consistent equity focus, and providing more comprehensive, actionable guidance for undertaking equitable scaling of public health innovations.