Biological plausibility is whether a proposed causal relationship makes sense given current understanding of disease mechanism.

Differential diagnosis is the clinical method of identifying the most probable cause of a condition by systematically excluding alternatives.

An idiopathic condition arises from unknown causes, providing an alternative explanation where exposure causation is alleged.

Medical causation is the link between the defendant's conduct or product and the claimed injury, established through expert medical testimony.

Multifactorial causation describes disease arising from multiple interacting factors rather than a single cause.

Temporal relationship requires that exposure precede disease by an interval consistent with the known latency.