Validation and validity of verbal autopsy procedures

Excerpt

Methods for interpreting verbal autopsy (VA) that have been validated fall into two major categories: (1) physician-certified verbal autopsy (PCVA), the commonly-used method in which one or more physicians ascertain causes of death based on their clinical judgment; and (2) computerized coding of verbal autopsy (CCVA), in which causes of death are derived using predefined criteria. Decision rules for CCVA can be expert opinion-based or data driven. The accuracy of these VA interpretation methods varies depending on causes of death per se, while the effect of misclassification error in VA on the estimates of cause-specific mortality fractions (CSMF) depends on the distribution of causes of death. The importance of acknowledging the effects of misclassification of causes of death by VA has been highlighted by the recent controversial estimates of malaria mortality in India [1]. The parameters of validity of VA obtained from a validation study may be useful to measure the uncertainty limits of CSMFs due to misclassification errors of VA, and in some contexts, to adjust the estimate of CSMF for the effect of misclassification error [2, 3]. …