[Confounding bias due to indication and severity in observational studies]

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Javier Nuevo1, Mónica Tafalla, Luis Cordero

  • 1Departamento Médico, AstraZeneca Farmacéutica Spain SA, Madrid, España. javier.nuevo@astrazeneca.com

Gaceta Sanitaria
|March 8, 2011
PubMed

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