Population-based versus hospital-based controls: are they comparable?

Alberto Ruano-Ravina1, Mónica Pérez-Ríos, Juan Miguel Barros-Dios

  • 1Department of Preventive Medicine and Public Health, University of Santiago de Compostela, Spain. alberto.ruano@usc.es

Gaceta Sanitaria
|December 17, 2008
PubMed
Abstract

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