The Relevance Ratio : Evaluating the Probative Value of Expert Testimony in Child Sexual Abuse Cases

Part II defines the relevance ratio and explains its relation to probabilistic reasoning. Part Ill uses the ratio to explore the ways in which physicians have misused the term "consistent with sexual abuse" in child abuse cases. Part IV considers whether symptoms "consistent with sexual abuse," although irrelevant for the purpose of proving abuse, may nevertheless be admissible for rebutting the assertion that abuse did not occur. Part V uses the relevance ratio to show that symptoms that are common among abused children may nonetheless have little if any relevance for proving that abuse occurred. Part VI discusses the relevance of clusters of symptoms and reveals ways in which clusters are likely to be less relevant than often believed. Part VII outlines the methodological limitations of existing research on the symptoms of child sexual abuse and explains why they may lead to poor estimates of the relevance ratio. Part VIII uses the relevance ratio to demonstrate that probative asymmetries exist between the presence and absence of various symptoms. Part IX discusses the significance of the existence of symptoms among nonabused children for understanding the significance of those symptoms among abused children