Fig. 3From: Heat stroke admissions during heat waves in 1,916 US counties for the period from 1999 to 2010 and their effect modifiersSpatial variation of (a) the relative risk (RR) of heat stroke on heat wave days compared to matched control days, and (b) the average number of heat wave days per county per year across the climate regions (the error bars represent one standard deviation). The model controlled for indicator variables of year and day of the weekBack to article page