New research by Steven Levitt (of Freakonomics fame) and John List has shown many of the findings to be not just questionable, but plain wrong. As Levitt says in a blog post in the New York Times:
We find that there actually wasn't a Hawthorne Effect in the original data, at least not of the sort that you read about in virtually every introductory psychology textbook, where it is claimed that the workers' output went up every time the lighting was changed, whether the change was to make the lights brighter or dimmer.
Evidence, science, learning and performance
The fall of the Hawthorne Effect should make us all stop and consider the founding principles that we apply to initiatives at work. In fact, many of the theories and concepts underpinning how modern organisations view performance are based on some pretty old research. What's more, the basis for some of the founding principles that we use to effect change, create conditions for optimal performance and develop new skills, are simply lost in the mists of time. Levitt and List's research highlights that we should be quite sceptical when it comes to fads. Look at the evidence for many learning theories and you will find them to be based on junk research. Examine in detail the basis of NLP, many of the brain training and accelerated learning initiatives and you'll find that there's about as much basis for them in science as a shampoo commercial. This is not to say that there's nothing of worth in these concepts; some of them definitely have some kind of positive effect. But, what we can't be sure of is which aspects have a positive effect and which have none. We certainly shouldn't give them false credibility by quoting science-y sounding evidence for their efficacy. Application of an analytical eye, background research and common sense can weed out the most egregious offenders (of which Brain Gym, Myers-Briggs and the Left-Right/Creative-Analytical brain theories are notable examples). I'll admit, I never thought to question the Hawthorne Effect myself. It was such a famous study that it was just accepted. Be sure, however, that I'm now going to look over the evidence for some of the more important social research findings such as the Pygmalion Effect and Placebo Effect. There's some excellent coverage of Levitt and List's Hawthorne Effect research in both the Economist, and in Tim Harford's column in the Financial Times: