This Microsoft-prevalence-based analysis report is supplementary to AV-Comparatives’ main report, already published, of the March 2016 File-Detection Test. No additional testing has been performed; rather, the existing test result have been re-analysed from a different perspective, to consider what impact the missed samples are likely to have on customers, according to telemetry data of Microsoft.
Microsoft commissioned this supplementary report. In this report, customer impact is measured according to prevalence. Essentially, some malware samples pose a greater threat to the average user than others, because they are more widespread. An impact heatmap can be found on https://impact.av-comparatives.org
More information can be read also in this here.