The Hawthorne effect

The Hawthorne effect 'The consumer of knowledge can never know what a dicky thing knowledge is until he has tried to produce it'; F. J. Roethlisberger, investigator at Hawthorne.The Hawthorne effect is a familiar anecdote to occupational physicians given that it relates to experiments with improved factory lighting which increased the productivity of workers.Incrementally increasing the level of lighting brought about increased output until someone reduced the level below baseline and output increased still further.The moral of the Hawthorne effect is that people change their behaviour when they think you are watching it and this principle has wider implications in medicine to describe the improved health of control groups.But how many of us know the origins of the fable?Gale [1] recounts the story and its background in a fascinating piece of occupational medicine archaeology: 'The story relates to the first of many experiments performed at the Hawthorne works of the Western Electric Company in Chicago from November 1924 onwards.The original aim was to test claims that brighter lighting increased productivity, but uncontrolled studies proved uninterpretable.The workers were therefore divided into matched control and test groups and, to the surprise of the investigators, productivity rose equally in both.In the next experiment, lighting was reduced progressively for the test group until, at 1.4 foot-candles, they protested that they could not see what they were doing.Until then the productivity of both groups had once again risen in parallel.The investigators next changed the light bulbs daily in the sight of the workers, telling them that the new bulbs were brighter.The women commented favourably on the change and increased their workrate, even though the new bulbs were identical to those that had been removed.This and other manoeuvres showed beyond doubt that productivity related to what the subjects believed, and not to objective changes in their circumstances.These at least seem to be the main facts behind the popular legend, although these particular experiments were never written up, the original study reports were lost, and the only contemporary account of them derives from a few paragraphs in a trade journal'.This paper examines the social, political and industrial background to these experiments which took place in a rapidly industrializing United States following the doctrine of Taylor and with huge immigration from Europe to man the factories.The Hawthorne experiments continued for a number of years before the factory collapsed catastrophically in the depression of 1932; Western Electric's turnover reduced from $411 million in 1929 to $70 million and 80% of the workforce lost their jobs.The story looks at the women who were studied (and who became celebrities as a result), the investigators, the academic industry that was born and the wider implications for medicine today.Ultimately, it is the researched who stand out rather than the researchers; five young women entered the folklore of sociology because they got faster and faster at making telephone relays.Their work also entered the folklore of medicine, as an 'effect' that everyone refers to, but no one can source or define.The complete article is accessible through the QJM website (www.qjmed.oxfordjournals.org).