Implementation science frameworks for evaluating primary health care interventions in low- and middle-income countries: a scoping review

Primary Health Care (PHC) is understood and operationalized in multiple ways, and this variability complicates how implementation is assessed in low- and middle-income countries (LMICs). We conducted a scoping review to map how PHC-oriented interventions in LMICs have been evaluated using the Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) framework and other implementation science approaches. Eighteen eligible articles were included. The interventions covered prevention, early detection, and management of chronic communicable and non-communicable conditions, in addition to maternal, child, and mental health. Most studies reflected selective PHC models, and Africa contributed the largest share of publications. RE-AIM was explicitly applied in seven studies; the remaining articles used other implementation science frameworks, most often within mixed-method designs. Overall, findings aligned with the stated study designs and generally followed appropriate reporting practices. This review offers a pragmatic map of how implementation science frameworks are being used to evaluate PHC interventions across LMIC setting.