Understanding health innovation adoption: A realist evaluation of pulse oximeter implementation in primary care for children under five in four West African countries

IntroductionHypoxemia is an important contributor to child mortality, particularly in low-resource settings where diagnostic tools are scarce. The AIRE project introduced pulse oximeters (POs) into 202 primary healthcare centres (PHCs) in Burkina Faso, Guinea, Mali, and Niger, integrating them into the Integrated Management of Childhood Illness (IMCI) guidelines. This initiative aimed to strengthen diagnostic capacities for identifying hypoxemia and to improve care management for critically ill children under five. This study examined how healthcare workers (HCWs) adopted POs and explored the contexts and mechanisms influencing their adoption. MethodsWe conducted a realist evaluation to analyse adoption patterns, focusing on interactions between the Intervention, Contexts, Actors, Mechanisms, and Outcomes (ICAMO configurations). Data collection included 299 interviews with HCWs, patients families, and institutional actors, conducted in 16 selected PHCs, at the institutional level, and in district hospitals, complemented by site observations. Analysis was performed using NVivo software, identifying ICAMO configurations as demi- regularities to explain variations in PO use and adoption. ResultsTraining enabled HCWs to recognize the utility of POs, further motivating their use. Support-focused supervision fostering a sense of support, while control-focused approaches sometimes resulted in mechanical use driven by external pressure. In contexts of high workloads and childrens agitation, difficulties in using POs were observed. In settings with limited diagnostic tools, POs increased HCWs diagnostic confidence, encouraging adoption and improving decision-making. Observing or knowing the benefits of POs on childrens health provided HCWs with a sense of relief and pride, further reinforcing PO adoption. However, structural barriers and challenges related to institutional adoption may threaten long-term use. ConclusionThis study highlights the necessary conditions for adopting POs in PHCs. While widely used by healthcare workers, addressing challenges related to training, supply chain logistics, and referral systems to hospitals is essential to ensure long-term sustainability and improve child health outcomes. What is already known on this topicO_LISevere hypoxemia significantly contributes to child mortality, especially in low- resource settings lacking adequate diagnostic tools. C_LIO_LIPulse oximeters (POs) are effective in detecting hypoxemia and guiding referrals, particularly when integrated into the Integrated Management of Childhood Illness (IMCI) guidelines. C_LI What this study addsO_LIUsing a realist evaluation approach, this study identified diverse responses to PO implementation, explaining the reasons for non-use, mechanical use, use, and adoption. POs appear to be predominantly adopted at an individual level. C_LIO_LIFindings highlight the critical role of boosting confidence in health care providers diagnostics, as well as the sense of relief and pride derived from participating in the care of children, to support adoption. C_LIO_LIStructural and institutional challenges, including training, supply chain issues, device maintenance, and referral system inadequacies, were found to potentially hinder the sustainability of PO adoption. C_LI How this study might affect research, practice, or policyO_LIThe study provides valuable insights into the contexts and mechanisms that facilitate or hinder the adoption of POs, which may also inform the integration of other diagnostic tools into primary healthcare systems. C_LIO_LIPolicymakers and healthcare implementers can utilize these findings to design tailored strategies to implement similar interventions in other contexts. C_LI