Careful calculation or a leap of faith? A field study of the translation of CBCA ratings to final credibility judgements

摘要

This field experiment investigated the influence of Criteria-Based Content Analysis (CBCA) ratings on ultimate decision accuracy regarding the credibility of children's statements of sexual abuse. Following a selection procedure, based on case facts independent of statement quality, 21 truthful accounts and 10 fabricated accounts of 6- to 17-year olds were analysed. Two experts rated the presence of the CBCA criteria and made overall credibility judgements for each statement. Rater one achieved an overall hit rate of 84% (95% for truthful statements and 60% for fabricated statements) and rater two a hit rate of 81% (81% for both truthful and fabricated statements) but the raters did not always agree. The CBCA criteria appeared more often in the truthful statements compared to the fabricated statements. Additional factors that influenced raters' credibility judgements, besides CBCA scores, are discussed.