I tried to do the math once to figure out if Japan would have been better off building a coal power plant instead of Fukushima, the nuclear plant that had the worst disaster in any western country. It was a surprisingly tough question.
Those studies of coal plant deaths are basically only counting people who died in mining disasters or were killed while operating the power plant. If you add in climate change effects, air pollution including radiation from flyash, and groundwater pollution the figure is almost certainly much worse; but also very hard to calculate with any certainty.