Milsten, A.M., Seaman, K.g., Liu, P., et al. (2003). Variables Influencing Medical Usage Rates, Injury Patterns, and Levels of Care for Mass Gatherings. (Abstract only.) Prehospital and Disaster Medicine. 18(4):334-46.
The authors examined medical utilization rates during three types of mass gatherings over a three-year period. They found that event type and temperature best predicted specific injuries and medical utilization rates.