Effectiveness of influenza vaccine in the community-dwelling elderly.

@article{Nichol2007EffectivenessOI,
  title={Effectiveness of influenza vaccine in the community-dwelling elderly.},
  author={Kristin L. Nichol and James D. Nordin and David B. Nelson and John Mullooly and Eelko Hak},
  journal={The New England journal of medicine},
  year={2007},
  volume={357 14},
  pages={
          1373-81
        }
}
BACKGROUND Reliable estimates of the effectiveness of influenza vaccine among persons 65 years of age and older are important for informed vaccination policies and programs. [] Key MethodMETHODS Data were pooled from 18 cohorts of community-dwelling elderly members of one U.S. health maintenance organization (HMO) for 1990-1991 through 1999-2000 and of two other HMOs for 1996-1997 through 1999-2000.

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