How can we calculate the “E” in “CEA”?

How can we calculate the “E” in “CEA”?

Bollinger, Lori A
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Volume:
22
Language:
english
Journal:
AIDS
DOI:
10.1097/01.aids.0000327623.31856.45
Date:
July, 2008
File:
PDF, 112 KB
english, 2008
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