Evaluation of the Effectiveness of an Intervention to Reduce Gaps in Hypertension Care in Low-income Medellin, Colombia

A multi-component intervention was designed based on international guidelines, a cross-sectional population survey results, and consultation with the community and institutional stakeholders. Three main components integrate activities related to (I) Health services redesign, (II) Clinical staff training (III) Patient and community engagement. The effectiveness of the intervention will be evaluated in a controlled before-after quasi-experimental study, with two deprived Communes of the city selected as intervention and control arms. Two representative population-based surveys of adults aged 35 years or older will be undertaken in the intervention and the control Communes two years apart, one before the intervention implementation and the other after. The surveys will include different adults. The main outcomes assessed will be the gaps in hypertension diagnosis, treatment, follow-up and control. Effectiveness will be evaluated with "difference in difference" measures. Generalized estimation equations models will be fitted considering the clustered nature of data and adjusting for potential confounding variables. The implementation process will be studied with mixed methods. Finally, implementation fidelity will be documented to assess to which degree the components of the intervention were implemented as intended.