AU  - Fisman DN
TI  - TO rule out confounding, observational studies of influenza vaccine need to include analyses during the “preinfluenza period”—reply
PT  - JOUR
DP  - 2007
TA  - Archives of Internal Medicine
pages = {1554-1555},
VI  - 167
IP  - 14
AID  - 10.1001/archinte.167.14.1554 [doi]
4100  - http://dx.doi.org/10.1001/archinte.167.14.1554
SO  - Archives of Internal Medicine July 23, 2007 167(14):1554