In September, we reported on a charming little study that found people who feel blue after watching sad videos have a harder time perceiving colors on the blue-yellow axis.
Now the researchers may be feeling blue themselves. On Thursday they retracted their study, saying that errors in how they structured the experiment skewed the results.
Shortly after the study was published online, commenters started looking skeptically at the results. And because the researchers had posted their data online, those commenters were able to run the numbers themselves. They didn't like what they found.
As one blogger wrote:
"A major problem is that the authors are claiming that they've found an interaction between video condition and color axis, but they haven't actually tested this interaction, they've just done a pair of independent t-tests and found different results."
As the indefatigable crew at the Retraction Watch blog points out, it's not the first time scientists have messed this up.
"This exact experimental oversight occurs all too often, according to a 2011 paper in Nature Neuroscience, which found that the same number of papers performed the procedure incorrectly as did it correctly."
And there were other problems, too, such as not testing participants' color perception before the study. Arguably this is the sort of thing that should have been caught by the authors' advisers and by the journal reviewers. But there's a lot of iffy science published in peer-reviewed journals that never gets retracted.
The editor of Psychological Science, the journal that published the study, gave the authors props for having owned up to their mistakes and retracting the work swiftly:
"Although I believe it is already clear, I would like to add an explicit statement that this retraction is entirely due to honest mistakes on the part of the authors."
The authors, Christopher Thorstenson, a graduate student in psychology at the University of Rochester, and colleagues Adam Pazda and Andrew Elliot, say that they plan to do the experiment over:
"We remain confident in the proposition that sadness impairs color perception, but would like to acquire clearer evidence before making this conclusion in a journal the caliber of Psychological Science."
Embarrassing as this must have been, in some ways this is a good news story for science. Independent scientists put a lot of time into uncovering the errors, and the authors and the journal fessed up and pledged to do better.
And no one's going to get the wrong medical treatment or die because of the errors. It just might make us a little more, well, blue.