Methodology

The methodology for this research was designed to generate new and actionable insights through the application of implementation science methods to selected Global Health Exemplar countries.

This was done by identifying and evaluating the steps countries used to decide on policies and evidence-based interventions to reduce under-five mortality and to execute their implementation strategies.

In addition, researchers sought to identify any contextual factors that either obstructed or facilitated the implementation of evidence-based interventions within these countries during the 2000–2016 study period.

In collaboration with the University of Global Health Equity (UGHE) team and with support from Gates Ventures, the team carried out a desk review of published materials, and documents produced outside of formal commercial or academic channels (so-called “gray literature”) related to Senegal’s general political, cultural, and economic context, and to the evidence-based interventions the country implemented to reduce under-five mortality.

The UGHE team collaborated with the Institute of Population, Development, and Reproductive Health (Cheikh Anta Diop University, Senegal) to conduct and analyze 23 key informant interviews with Senegal’s policy makers and implementation partners, and with health officials at the national and local levels.

The team also drew upon analyses from the International Center for Equity in Health (Federal University of Pelotas, Brazil) and geospatial mapping from the Institute for Health Metrics and Evaluation (University of Washington, USA) to understand changes in health equity over time.

Project Framework

Both the desk review research and the key informant interviews were informed by an implementation science framework designed specifically for this project. While it is often possible to identify policies and evidence-based interventions chosen by a country to reduce under-five mortality, the key lessons in how these were chosen, adapted, implemented, and sustained are often missing from available published or gray literature.

Because the same policies and interventions often produce different results in different countries, implementation science offers important tools for how to think more holistically about how and why countries were able to reduce under-five mortality, and from where lessons in replication can be drawn.

To guide the overall work, we developed a framework to understand the contribution of contextual factors at varying levels, from the country as a whole to specific communities and even individual facilities. This approach combines elements of existing frameworks, notably the Exploration, Preparation, Implementation, and Sustainment (EPIS) process by Aaron and colleagues (2011); and implementation outcomes (feasibility, fidelity, acceptability, reach, and effectiveness) by Proctor and colleagues (2010).^1 2 We also added a new step – Adaptation – to the EPIS framework, resulting in the modified abbreviation of EPIAS.

Desk Review

In collaboration with UGHE and Gates ventures, the University of Washington Strategic Analysis, Research and Training (START)Center undertook an extensive review of available information and published data on under-five mortality in Senegal. Gates Ventures researchers conducted initial research through MEDLINE (PubMed) and Google Scholar using the search terms “child mortality” or “under-5 mortality” and “Senegal.” Further searches included specific evidence-based interventions, causes of death, or contextual factors as search terms (e.g. “insecticide-treated nets,” “malaria,” or “community health workers”).

The desk review was an iterative process, with ongoing additions occurring throughout the initial research and case-study development processes as additional sources (published articles, reports, case studies, policy papers, and other country documents) were identified. Researchers explored the various non-health care interventions that may have contributed to under-five mortality reduction. These included education, poverty reduction, water and sanitation access, and programs designed to improve nutritional status.

Following these initial steps, the UGHE team expanded the review to incorporate additional published literature and other relevant documents relevant to the overall research.

Key Informant Interviews

In collaboration with the Institute of Population, Development, and Reproductive Health at Cheikh Anta Diop University in Dakar, we identified key informants reflecting a broad range of experience and viewpoints. These individuals were chosen based on the topics identified in the desk review and through other analyses, with an emphasis on potential interviewees who could provide information on the EPIAS stages during the period of study.

Our roster of interviewees ultimately included current and former Ministry of Health employees responsible for high-level strategic direction, or for its responses to specific disease or intervention areas. The list also included implementing partners and officials from other multilateral agencies and donor organizations.

While we specifically sought interviewees who had been active in Senegal’s interventions to reduce under-five mortality during the study period, we were also able to capture some valuable information for the periods of 1995–2000 and 2016–2019.

The interviews were designed to address the evidence-based interventions implementation process, from exploration to preparation, implementation, adaptation, and sustainment. This includes critical contextual factors at the relevant global, national, ministry, and local levels. The interviews also identified additional sources of data and information that could be added to the knowledge base and understanding already developed from the desk review.

All interviews themselves were led by the project principal investigators (Agnes Binagwaho and Lisa Hirschhorn) or by in-country team leads. Following the close of the interviews, notes were combined and recordings (if allowed) were used to clarify areas as needed. Interviews were conducted in French or English, depending on the preferred language of the interviewee.

Interviews were coded using NVivo software (version 12), and reviewed by at least one of the principal investigators for accuracy and the framework was used to extract the EPIAS steps, implementation strategies, implementation outcomes, and contextual factors. A priori codes for contextual factors and strategies were adapted and expanded as emerging themes were identified.

Analysis and Synthesis

The UGHE team used a mixed-methods explanatory approach, applying the framework to understand the progress (or lack thereof) for each cause of death and coverage of chosen evidence-based interventions, and facilitators and barriers at the local, national, and global levels.

This approach was designed to understand how and why Senegal was able to achieve success in reducing under-five mortality, and the primary obstacles it faced. The analyses were also informed by previous projects, including Countdown 2015, equity analyses from the International Center for Equity in Health, and geospatial mapping from the Institute for Health Metrics and Evaluation, among others.

The research team also collaborated with the Institute for Health Metrics and Evaluation (IHME) to look at quantitative modeling results using a decomposition method, and also collaborated with the Johns Hopkins Bloomberg School of Public Health to model results using the Lives Saved Tool (LiST).These quantitative analyses complement the primary research by looking at what the models suggest about the likely contribution of specific interventions in reducing child mortality.

The decomposition analysis conducted by IHME breaks down changes over time for a series of factors that directly influence child mortality levels using the Das Gupta method. The overall change in mortality between years is divided into contributions from:

• Interventions and risk factors: Interventions and risk factors influence mortality rates through changes in the proportion of the population exposed to each, and through changes in their corresponding relative risks of mortality. Increased coverage of specific interventions is known to reduce mortality rates, whereas increased exposure to certain risk factors increases mortality rates. The relative risk for each specific disease outcome is established through a literature review.
• Population changes: The total number of deaths in a given year is a product of both age-specific mortality rates and the population size in each age group, so changes in both population growth and population age structure are factored into the decomposition. One example of the effect of population changes is if mortality rates are cut in half while the population size doubles in each age group, total deaths remain the same.

The Lives Saved Tool (LiST), developed by the Johns Hopkins Bloomberg School of Public Health, calculates changes in cause-specific mortality based on intervention coverage change, intervention effectiveness for that cause, and the percentage of cause-specific mortality sensitive to that intervention. Coverage data come from large-scale household surveys – typically Demographic and Health Surveys (DHS) and Multiple Indicator Cluster Surveys (MICS), as well as WHO/UNICEF and the WHO/UNICEF Joint Monitoring Programme for Water Supply, Sanitation and Hygiene (JMP).

Default effectiveness values come from systematic reviews, meta-analyses, Delphi estimations, and randomized control trials based upon the Child Health Epidemiology Reference Group guidelines. Baseline mortality is drawn from country-level estimates from DHS, WHO, UNICEF, UNFPA, World Bank Group, and the United Nations Population Division and the UN Inter-Agency Group for Child Mortality Estimation (IGME). Additionally, users who have more recent or alternative data sources can easily replace default data with their own.

Human Subjects Review

The work was approved by the National Ethics Committee for Health Research at Senegal’s Ministry of Health. The ethics review committees of University of Global Health Equity and Northwestern University also approved the study.

Interviewees were informed about the goals and structure of the project, and their consent for participation and recording was obtained separately from the interview itself.

No quotes or specific viewpoints that might be attributable to an individual source were included in the interview record without explicit permission. All recordings and interviews were kept in password-protected computers and stored on a limited-access Google Drive, with interviewees’ names removed. All recordings were destroyed once interview coding had been completed.