Michael, J. and Barbera, J.A. (1997). Mass Gathering Medical Care: A Twenty-Five Year Review. (Abstract only.) Prehospital and Disaster Medicine. 12(4): 72-79.
The authors examined international mass gathering literature to better understand the relationship between size of the gathering and the frequency of patients seeking medical aid. Events that took place on hot weather days had higher numbers of patient visits and statistically more cardiac events occurred at sporting and papal events.