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Hawthorne Effect

  1. Mitchell H. Gail

Published Online: 15 JUL 2005

DOI: 10.1002/0470011815.b2a03069

Encyclopedia of Biostatistics

Encyclopedia of Biostatistics

How to Cite

Gail, M. H. 2005. Hawthorne Effect. Encyclopedia of Biostatistics. 4.

Author Information

  1. National Cancer Institute, Bethesda, MD, USA

Publication History

  1. Published Online: 15 JUL 2005


The Hawthorne effect is an effect on study participants, which results from their knowing that they are being studied. It can bias estimates of true exposure effects.


  • Hawthorne effect;
  • exposure effect;
  • bias