Table 5.

Summary of key review findings on factors influencing scale-up of public health interventions in LMICs and their confidence

Summary key review finding	Number of studies	Studies contributing	Overall confidence
Factors influencing a change in structure
Advocacy: Involvement of champions at local and national levels is a facilitator of the scale-up of public health interventions. Advocacy is necessary to raise attention for the problem that will be addressed by the intervention, to facilitate policy changes in favour of the intervention, to acquire financial support for scale-up, to address health systems’ gaps that could hinder scale-up and to facilitate political will.	19	Das et al. (2018), Araya et al. (2012), Ghiron et al. (2014), Gergen et al. (2018), Goga and Muhe (2011), Hainsworth et al. (2014), Igras et al. (2014), Jordan et al. (2016), Krumholz et al. (2015), MacGregor et al. (2018), Omimo et al. (2018), Pérez-Escamilla et al. (2018), Schneider et al. (2010), Somassè et al. (2013), Spicer et al. (2016, 2018), Svanemyr et al. (2015), Wickremasinghe et al. (2018), Yothasamut et al. (2010), Yamey (2012)	High confidence: Minor concerns regarding methodological limitations. No or very minor concerns about coherence and adequacy. Minor concerns regarding relevance.
Resources: Financial, human and material resources and time are factors influencing the scale-up of public health interventions. Inadequate estimating and securing of financial resources (from governments of donors) are main factors hindering scale-up, leading to limited funding available for training, supervision and human resources and limited ability to react to unforeseen costs. Implementation capacity can hinder scale-up, especially in contexts in which other factors make scale-up more difficult.	22	Araya et al. (2012), Bellows et al. (2016), Blauvelt et al. (2018), Fitzgerald et al. (2016), Gergen et al. (2018), Ghiron et al. (2014), Goga and Muhe (2011), Hainsworth et al. (2014), Krumholz et al. (2015), MacGregor et al. (2018), Ojomo et al. (2015), Omimo et al. (2018), Pérez-Escamilla et al. (2018), Schneider et al. (2010), Somassè et al. (2013), Spicer et al. (2016), Svanemyr et al. (2015), Wickremasinghe et al. (2018), Yamey (2012), Yothasamut et al. (2010), Spicer et al. (2014) and Spicer et al. (2018)	Moderate confidence: Minor concerns regarding methodological limitations. Minor concerns about coherence, relevance and adequacy.
Political will: Political will at national, regional and district government levels is a facilitator for the scale-up of public health interventions. Political will could be enhanced through alignment of the intervention with priority policies, advocacy, sharing of evidence and collaboration/involvement of the government from the start.	12	Bellows et al. (2016), Fitzgerald et al. (2016), Gergen et al. (2018), Hainsworth et al. (2014), Jordan et al. (2016), Krumholz et al. (2015), MacGregor et al. (2018), Schneider et al. (2010), Spicer et al. (2016), Spicer et al. (2018), Svanemyr et al. (2015) and Yamey (2012)	Moderate confidence: Minor concerns regarding methodological limitations and relevance. Moderate concerns about relevance. Data not sufficiently rich (adequacy).
Supply chain: Inadequate supply chains form barriers to the scale-up of public health interventions, because of the unavailability of products necessary for the intervention to be scaled	9	Ansbro et al. (2015), Bellows et al. (2016), Ghiron et al. (2014), Jordan et al. (2016), Krumholz et al. (2015), MacGregor et al. (2018), Ojomo et al. (2015), Schneider et al. (2010) and Spicer et al. (2016)	Moderate confidence: Minor concerns regarding methodological limitations. No or minor concerns about relevance and coherence. Data not sufficiently rich (adequacy).
Policies/guidelines: Alignment of public health interventions with existing policies or guidelines can facilitate scale-up. (Changes in) policies or guidelines on health financing and human resources can hinder or facilitate the scale-up of a public health intervention.	7	Fitzgerald et al. (2016), Igras et al. (2014), MacGregor et al. (2018), Somassè et al. (2013), Spicer et al. (2016), Spicer et al. (2018) and Wickremasinghe et al. (2018)	Moderate confidence: Minor concerns about methodological limitations. No or very minor concerns regarding coherence and relevance. Moderate concerns regarding relevance.
Characteristics of the intervention: In many cases, the simplicity of a public health intervention facilitates scale-up. In addition, the relevance and importance, (cost)-effectiveness, acceptability, alignment with existing systems, sustainability and adaptability of a public health intervention can facilitate its scale-up.	22	Araya et al. (2012), Bellows et al. (2016), Fitzgerald et al. (2016), Ghiron et al. (2014), Goga and Muhe (2011), Hainsworth et al. (2014), Igras et al. (2014), Jordan et al. (2016), Keyonzo et al. (2015), Krumholz et al. (2015), MacGregor et al. (2018), Ojomo et al. (2015), Omimo et al. (2018), Pappa et al. (2015), Pérez-Escamilla et al. (2018), Schneider et al. (2010), Somassè et al. (2013), Spicer et al. (2014), Spicer et al. (2018), Svanemyr et al. (2015), Yamey (2012) and Yothasamut et al. (2010)	Low confidence: Moderate concerns regarding methodological limitations and coherence. Minor concerns about relevance. Data not sufficiently rich (adequacy).
Health systems and governance: Weak health systems and governance are barriers to the scale-up of public health interventions, due to delays, corruption, limited infrastructure and resources. However, embedment of interventions within the existing health system can enhance scale-up.	9	Keyonzo et al. (2015), Omimo et al. (2018), Pérez-Escamilla et al. (2018), Spicer et al. (2016), Spicer et al. (2014), Svanemyr et al. (2015), Wickremasinghe et al. (2018), Yamey (2012) and Jordan et al. (2016)	Low confidence: Minor concerns regarding methodological limitations. No or very minor concerns about relevance. Serious concerns regarding coherence and adequacy: data are not rich and finding is identified by a limited number of articles.
Factors influencing a change in practice
Strategy: The availability of a strategic plan for scale-up, which is to be monitored and adapted over time, can facilitate the scale-up of public health interventions, as it enables strategic choices regarding training, supervision, political timing, implementation areas, targets for expansion and the allocation of resources for scale-up.	9	Gergen et al. (2018), Hainsworth et al. (2014), Jordan et al. (2016), Keyonzo et al. (2015), MacGregor et al. (2018), Omimo et al. (2018), Spicer et al. (2014), Spicer et al. (2018) and Yamey (2012)	High confidence: Minor concerns regarding methodological limitations and adequacy. No or very minor concerns regarding coherence and relevance.
Training and supervision: Insufficient or intermittent or ad hoc training and supervision forms a barrier to the scale-up of public health interventions and is related to inadequate funding and planning, high-staff turnover, lack of local expertise regarding supervision and lack of involvement of government representatives in curricula development.	15	Bellows et al. (2016), Ghiron et al. (2014), Goga and Muhe (2011), Hainsworth et al. (2014), Jordan et al. (2016), Keyonzo et al. (2015), Krumholz et al. (2015), MacGregor et al. (2018), Ojomo et al. (2015), Omimo et al. (2018), Schneider et al. (2010), Spicer et al. (2014), Spicer et al. (2018), Yothasamut et al. (2010) and Somassè et al. (2013)	Moderate confidence: Moderate concerns regarding methodological limitations. No or very minor concerns about coherence and adequacy. Minor concerns regarding relevance.
Collaborations: Different types of collaborations facilitate the scale-up of public health interventions, such as community participation, partnerships with actors that have access to specific groups and intra- and cross-sectoral collaboration at national level. A lack of these collaborations can hinder scale-up, partly through limited ownership.	22	Araya et al. (2012), Bellows et al. (2016), Blauvelt et al. (2018), Gergen et al. (2018), Ghiron et al. (2014), Hainsworth et al. (2014), Igras et al. (2014), Jordan et al. (2016), Keyonzo et al. (2015), MacGregor et al. (2018), Ojomo et al. (2015), Omimo et al. (2018), Pappa et al. (2015), Schneider et al. (2010), Somassè et al. (2013), Spicer et al. (2016), Spicer et al. (2014), Spicer et al. (2018), Svanemyr et al. (2015), Yamey (2012), Yothasamut et al. (2010) and Wickremasinghe et al. (2018)	Moderate confidence: Moderate concerns about methodological limitations. No or very minor concerns regarding coherence and adequacy. Minor concerns about relevance.
Research and Monitoring and Evaluation: The availability of research and monitoring and evaluation data facilitates the scale-up of public health interventions. Research data provide insight into the problem addressed by the intervention, which is useful for advocacy, and into the context in which scale-up takes place (before and during scale-up). Monitoring and evaluation also provides insight into context and possible implementation challenges. A lack of research can hinder scale-up, except in cases where political considerations play a major role.	18	Araya et al. (2012), Blauvelt et al. (2018), Fitzgerald et al. (2016), Gergen et al. (2018), Ghiron et al. (2014), Hainsworth et al. (2014), Igras et al. (2014), Jordan et al. (2016), Keyonzo et al. (2015), MacGregor et al. (2018), Schneider et al. (2010), Spicer et al. (2016), Spicer et al. (2014), Spicer et al. (2018), Wickremasinghe et al. (2018), Yamey (2012), Yothasamut et al. (2010) and Omimo et al. (2018)	Moderate confidence: Moderate concerns regarding methodological limitations. No or very minor concerns about coherence and adequacy. Minor concerns regarding relevance.
Politics: Politics influence the scale-up of public health interventions and can be both a barrier and a facilitator. Changes within ministries or political unrest could form a barrier to decision-making related to scale-up. However, political changes may also create a window of opportunity for scale-up, as there is a room for new directions/decisions.	10	Araya et al. (2012), Goga and Muhe (2011), Jordan et al. (2016), MacGregor et al. (2018), Spicer et al. (2016), Spicer et al. (2018), Yamey (2012), Yothasamut et al. (2010), Pérez-Escamilla et al. (2018) and Wickremasinghe et al. (2018)	Moderate confidence: Minor concerns regarding methodological limitations and coherence. Moderate concerns regarding adequacy and no or very minor concerns regarding relevance.
Leadership: Political and programme leadership can influence the scale-up of public health interventions. Political leadership depends on political will or buy-in and is, therefore, not always present, which hinders scale-up. Programme leadership, when present at different levels, facilitates scale-up.	4	Araya et al. (2012), Bellows et al. (2016), MacGregor et al. (2018) and Yamey (2012)	Moderate confidence: Minor concerns regarding methodological limitations. No or very minor concerns about relevance. Identified by a very limited number of articles (adequacy).
Factors influencing a change in culture
Sociocultural environment: The sociocultural environment can hinder the scale-up of public health interventions, as social and cultural norms, and preferences may influence the acceptance and support of the intervention when this intervention does not take the sociocultural environment enough into account.	7	Macgregor et al. (2018), Ojomo et al. (2015), Spicer et al. (2016), Spicer et al. (2014), Spicer et al. (2018), Svanemyr et al. (2015) and Yamey (2012)	Moderate confidence: Minor concerns regarding methodological limitations and coherence. No or very minor concerns about relevance. Data are not sufficiently rich, and finding is identified by a limited number of articles (adequacy).
Need/demand for intervention: When stakeholders at different levels feel that there is a need for the intervention based on available local data, this will facilitate the scale-up of public health intervention. When this need if not felt by (one of) the stakeholders, scale-up is constrained.	7	Araya et al. (2012), Ghiron et al. (2014), Jordan et al. (2016), Ojomo et al. (2015), Pérez-Escamilla et al. (2018), Somassè et al. (2013) and Spicer et al. (2018)	Low confidence: Minor concerns regarding methodological limitations. Moderate concerns regarding coherence and minor concerns about relevance. Data are not sufficiently rich, and finding is identified by a limited number of articles (adequacy).