The Bayesian Approach to Causality Assessment: An Introduction

Abstract

This paper outlines an approach to causality assessment that is based on the logic of uncertainty, Bayesian probability theory. The goal of causality assessment is taken to be the calculation of the posterior odds in favor of drug causation, given all available background and case information. There are two stages to the Bayesian approach: collecting the facts and evaluating the evidence. The evaluation proceeds by a series of probability assessments that decompose the overall causality assessment into a series of component evaluations, each of which focuses on one factor or source of information. The solutions to these component problems are then combined according to the rules of probability theory to give a solution to the overall causality assessment.