River roads and cardiac care: Multimodal geographic accessibility to PCI-capable facilities and acute myocardial infarction mortality in the Brazilian Legal Amazon
Year: 2026
Type: preprint
Study design: Study Protocol
Abstract: This project investigates whether greater multimodal geographic difficulty in reaching emergency-capable health facilities is associated with worse outcomes for acute myocardial infarction in remote populations of the Brazilian Legal Amazon. The study will construct a reproducible multimodal travel-time network integrating navigable rivers, roads, trails, ports and transfer points, transport modes, locally justified travel speeds, population locations, and health facilities with documented PCI capability. Particular attention is given to Amazonian transport systems, where rivers may function as transportation corridors rather than geographic barriers. Geographic accessibility will be distinguished from effective access to care, and no individual-level causal interpretation will be made. Network structure, transfer rules, facility eligibility, travel speeds, and validation procedures will be specified before epidemiological outcome modelling. The primary epidemiological application will examine acute myocardial infarction mortality using Brazilian administrative and vital-statistics data. Sensitivity analyses will evaluate network incompleteness, alternative multimodal assumptions, facility definitions, and geographic boundary effects. The project follows a reproducible workflow covering geospatial feasibility, novelty assessment, multimodal network construction and validation, protocol registration, spatial analysis, epidemiological modelling, sensitivity analyses, results lock, and manuscript preparation. Scripts, metadata, analytical decisions, and shareable derived outputs will be preserved to support reproducibility.
Language: English
Subfield: Cardiology and Cardiovascular Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W7204706978