Several methods and criteria are used to establish causal links:
1. Observational Studies: These include cohort studies and case-control studies that observe the association between exposure and outcomes over time. 2. Randomized Controlled Trials (RCTs): These are considered the gold standard for establishing causality as they minimize bias by randomly assigning subjects to exposed or non-exposed groups. 3. Bradford Hill Criteria: This set of principles helps determine causality, including strength, consistency, specificity, temporality, biological gradient, plausibility, coherence, experiment, and analogy.
