Casualty recorders must have a process of corroboration in place to evaluate the data they have collected. A process of corroboration will typically include two steps: the first step will be to assess the internal coherence of the information provided; the second to crosscheck the information with information provided by other sources.
When the connections between the arguments in a written or oral piece of information are logically assembled and make the information meaningful in a real world context, this is when a piece of information can be assessed as being internally coherent. Internal coherence implies, among other things, that the provided information is free of contradictions and avoids logical and similar fallacies which are damaging to the credibility of the information provided. Crosschecking is the attempt to confirm information with other information from independent sources. It seeks to confirm one piece of information by seeking to obtain information on the same topic from multiple other sources which are independent from one another. This includes different sources of the same type (for example three news articles from three different news outlets by different authors using different primary sources) but also different types of sources (for example corroboration through the comparison of video, media reports, and witness testimonies). The corroboration process can have a number of outcomes: it may confirm the original piece of information; lead to the assessment that no definitive conclusion is possible as different perspectives emerge and appear equally possible; or lead to a decision to reject the initial piece of information.
Standards for Casualty Recording, 2016, p. 25