This document discusses causality in epidemiology. It defines causality as involving evidence of variations or changes, rather than just regularities. Epidemiology aims to establish variational rather than regularity claims by studying how disease variability is influenced by exposure variability. Methodologies in epidemiology like observational studies measure and test variations to establish causal relationships.

1. Causality in Epidemiology definition – evidence – rationale Federica Russo Philosophy, Louvain & Kent

6. Variational claims in epidemiology goals definitions methodology