AU - Camp M, Chang DC, Zhang Y, et al TI - PRovider density and health system facility factors and their relationship to rates of pediatric perforated appendicitis in us counties PT - JOUR DP - 2010 TA - Archives of Surgery pages = {1139-1144}, VI - 145 IP - 12 AID - 10.1001/archsurg.2010.271 [doi] 4100 - http://dx.doi.org/10.1001/archsurg.2010.271 SO - Archives of Surgery December 1, 2010 145(12):1139