By Amy Costello

Jeremy Smith has written a new book called Epic Measures: One Doctor. Seven Billion Patients. It profiles the work of Christopher Murray, a Harvard-trained doctor and health economist who looked at a lot of numbers about how people live and die around the world and found that it's all a guess. Murray and his global team of computer scientists, number crunchers and medical specialists have devoted themselves to his "Global Burden of Disease" study, which traces and compares the sources of human death and suffering. The goal was to help channel aid dollars based on facts, not hunches.

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