@article{doi:10.1001/archinte.167.14.1554,
author = {Fisman DN},
title = {TO rule out confounding, observational studies of influenza vaccine need to include analyses during the “preinfluenza period”—reply},
journal = {Archives of Internal Medicine},
volume = {167},
number = {14},
pages = {1554-1555},
year = {2007},
doi = {10.1001/archinte.167.14.1554},
URL = { + http://dx.doi.org/10.1001/archinte.167.14.1554},
eprint = {/data/Journals/INTEMED/5604/ilt0723_1554_1555.pdf}
}