The West Virginia data from NPR and Boston University's study indicated a 13-fold undercount.
A bar graph with three bars is labelled "Average W.Va. Heat Deaths 2018-2025. The leftmost bar is labelled "CDC heat deaths" and reaches 4.1, the middle bar is labelled "Scaled modeled heat deaths" and reaches 52.8 and the rightmost bar is labelled "Difference (scaled - CDC)" and reaches 48.6