A proposed tendency for people to change their behaviour when they know they are being observed.
Reanalysis of the original Western Electric data from 1924-32 found little support for the effect as described — the productivity changes tracked other factors. The name survives the finding.
In practice
- A ward's hand-hygiene compliance rises the week the auditors are on site and settles back the week after.
- A pilot run by its own enthusiasts with the director visiting weekly outperforms the rollout, and nobody can say which of the two differences did it.
- Possible explanations
- One explanation is motivation: people work differently when they are watched and something appears to be at stake. Another is that observation usually arrives with other changes, including new equipment, management attention and feedback, which do the work the name gets credit for.
- In its favour
- Being studied does change behaviour in some settings: systematic reviews of trials find modest effects when participants know they are being observed.
- Against it
- The original Western Electric data do not support the effect as it is told, and the term is now used so loosely, for any change during a study, that it is hard to test.
- Standing
- Reanalysis of the original data found little support for the effect as described. Its mirror image in control groups is the John Henry effect.
- Further reading
- Wikipedia
- Subject
- Psychology & Behavior
- Essay
- A century and a half of measuring the mind