Process evaluation of a complex, multilevel, multicomponent scheme for the prevention and control of non-communicable diseases in Tamil Nadu, India: a mixed-methods protocol

Background : Non-communicable diseases (NCDs) are the leading cause of morbidity and mortality in India, necessitating development of multilevel and multicomponent interventions. Makkalai Thedi Maruthuvam (MTM) is a complex multilevel, multicomponent intervention developed and implemented by the south Indian State of Tamil Nadu. The scheme aims to deliver services for preventing and controlling diabetes, and hypertensionat doorstep. This paper describes the protocol for planning and conducting the process evaluation of the MTM scheme. Methods and analysis The process evaluation uses mixed methods (secondary data analysis, key informant interviews, in-depth interviews, conceptual content analysis of documents,facility-based survey and non-participant observation) to evaluate the implementation of the MTM scheme. The broad evaluation questions addressed the fidelity, contexts, mechanisms of impact and challenges encountered by the scheme using the Consolidated Framework for Implementation Research (CFIR) framework. The specific evaluation questions addressed selected inputs and processes identified as critical to implementation by the stakeholders. The CFIR framework will guide the thematic analysis of the qualitative interviews to explore the adaptations and deviations introduced during implementation in various contexts. The quantitative data on the indicators developed for the specific evaluation questions will be cleaned and descriptively analysed.