Chen SI, Wang Y, Dreyer R, Strait KM, Spatz ES, Xu X, Smolderen KG, Desai NR, Lorenze NP, Lichtman JH, Spertus JA, D'Onofrio G, Bueno H, Masoudi FA, Krumholz HM. Insurance and Prehospital Delay in Patients =55 Years With Acute Myocardial Infarction. Am J Cardiol. 2015 Dec 15; 116(12):1827-32.