Rating criteria of the causal nexus in Whiplash Associated Disorders: A study of interrater reliability

Abstract

IntroductionThe diagnosis of Whiplash Associated Disorders is subject to various criteria, some of a subjective nature, which impedes a high percentage of agreement among raters of the causal nexus. It is necessary to develop an evidence-based methodology to maximize the uniformity of this diagnosis. Our objective is to assess the interrater reliability of four experts in legal medicine who establish the causal nexus of traffic accident patients. Material and method300 traffic accident patients evaluated by 4 legal medicine experts. They conducted two ratings, one without and one with a study of the biomechanics of the accident. The degree of concordance of the ratings was studied by the intraclass correlation coefficient (ICC) and the concordance index (CI). ResultsThe results of both the intraclass correlation coefficient and the concordance index of the rating prior to the biomechanical study of the injury yield moderate-high values (ICC=.70; CI=.60). Likewise, the values observed in the rating with the study of biomechanics also indicate moderate-high agreement (ICC=.78, CI=.67). ConclusionsThe study of biomechanics slightly improves concordance. However, the aforementioned study does not help to reduce the proportion of doubtful cases and the levels of improvement are not acceptable. There are significant differences between the classifications, suggesting that the proposed valuation methodology is not uniform enough to reach a consensus.