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Nosocomial Infection, Length of Stay, and Time-Dependent Bias

  • Jan Beyersmann (a1) (a2), Thomas Kneib (a3), Martin Schumacher (a2) and Petra Gastmeier (a4)


Nosocomial pneumonia and its impact on length of stay are major healthcare concerns. From an epidemiological perspective, nosocomial pneumonia is a time-dependent event. Any statistical analysis that does not explicitly model this time dependency will be biased. The bias is not redeemed by adjusting for baseline information.


Corresponding author

Freiburg Centre for Data Analysis and Modelling, University of Freiburg, Eckerstrasse 1, Freiburg, D-79104, Germany(


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Infection Control & Hospital Epidemiology
  • ISSN: 0899-823X
  • EISSN: 1559-6834
  • URL: /core/journals/infection-control-and-hospital-epidemiology
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