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Time-dependent study entries and exposures in cohort studies can easily be sources of different and avoidable types

Martin Wolkewitz1, Arthur Allignol, Stephan Harbarth

  • 1Institute of Medical Biometry and Medical Informatics, University of Freiburg, Freiburg, Germany. wolke@imbi.uni-freiburg.de

Journal of Clinical Epidemiology
|September 29, 2012
PubMed
Abstract

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