BMJ Qual Saf 23:974-980 doi:10.1136/bmjqs-2014-003080
  • Original research

Quantification of the Hawthorne effect in hand hygiene compliance monitoring using an electronic monitoring system: a retrospective cohort study

Open AccessEditor's Choice
  1. Michael Gardam5,6
  1. 1Institute of Health Policy, Management & Evaluation, University of Toronto, Toronto, Ontario, Canada
  2. 2Department of Medicine, McMaster University, Hamilton, Ontario, Canada
  3. 3Infonaut Inc, Toronto, Ontario, Canada
  4. 4Faculty of Information, University of Toronto, Toronto, Ontario, Canada
  5. 5Department of Infection Prevention & Control, University Health Network, Toronto, Ontario, Canada
  6. 6Department of Medicine, University of Toronto, Toronto, Ontario, Canada
  1. Correspondence to Dr Jocelyn A Srigley, Department of Medicine, McMaster University, 711 Concession Street, M1-Room 8, Hamilton, ON, Canada, L8V 1C3; srigley{at}
  • Received 31 March 2014
  • Revised 20 June 2014
  • Accepted 21 June 2014
  • Published Online First 7 July 2014


Background The Hawthorne effect, or behaviour change due to awareness of being observed, is assumed to inflate hand hygiene compliance rates as measured by direct observation but there are limited data to support this.

Objective To determine whether the presence of hand hygiene auditors was associated with an increase in hand hygiene events as measured by a real-time location system (RTLS).

Methods The RTLS recorded all uses of alcohol-based hand rub and soap for 8 months in two units in an academic acute care hospital. The RTLS also tracked the movement of hospital hand hygiene auditors. Rates of hand hygiene events per dispenser per hour as measured by the RTLS were compared for dispensers within sight of auditors and those not exposed to auditors.

Results The hand hygiene event rate in dispensers visible to auditors (3.75/dispenser/h) was significantly higher than in dispensers not visible to the auditors at the same time (1.48; p=0.001) and in the same dispensers during the week prior (1.07; p<0.001). The rate increased significantly when auditors were present compared with 1–5 min prior to the auditors’ arrival (1.50; p=0.009). There were no significant changes inside patient rooms.

Conclusions Hand hygiene event rates were approximately threefold higher in hallways within eyesight of an auditor compared with when no auditor was visible and the increase occurred after the auditors’ arrival. This is consistent with the existence of a Hawthorne effect localised to areas where the auditor is visible and calls into question the accuracy of publicly reported hospital hand hygiene compliance rates.

This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:

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