Bradford Hill's 'Biological gradient (dose–response relationship)' as a measure of causation (one of several with temporality, biological plausibility etc.) STRONGLY seen in graph by Shrestha et al.
by Paul Alexander
Shrestha et al. examined effectiveness of COVID Bivalent booster & graph shows clear dose response & fits Bradford Hill's 'Biological gradient in pointing to causality; greater exposure=greater effect
Biological gradient (dose–response relationship): Greater exposure should generally lead to greater incidence of the effect.