A Lesson from the Power Pose Debacle

Amy Cuddy’s TED talk on power posing has thirty-seven million views. Its main idea is simple: if you adopt an expansive, authoritative pose, your actual power will increase. For evidence, Cuddy refers to a study she conducted in 2010 with Dana Carney and Andy Yap. Holes and flaws in the study have since been revealed, but Cuddy continues to defend it. But why not work with the flaws, give them full attention and acknowledgment, and proceed from there?

Recently TED and Cuddy appended a note to the summary of the talk: “Some of the findings presented in this talk have been referenced in an ongoing debate among social scientists about robustness and reproducibility.” In other (and clearer) words: The power pose study has not held up under scrutiny. At least two replications failed; Andrew Gelman, Uri Simonsohn, and others have critiqued it robustly; and Carney, the lead researcher, detailed the study’s flaws—and disavowed all belief in the effect of power poses—in a statement posted on her website. Jesse Singal (New York Magazine) and Tom Bartlett (The Chronicle of Higher Education) have weighed in with analyses of the controversy.

Very well, one might shrug aloud, but what should we, irregular members of the regular public, do? Should we distrust every TED talk? Or should we wait until the experts weigh in? Neither approach is satisfactory. When faced with fantastic scientific claims, one can wield good skepticism and follow one’s doubts and questions.

Before learning of any of this uproar, I found Cuddy’s talk unstable. Instead of making a coherent argument, it bounces between informal observations, personal experiences, and scientific references. (Granted, many TED talks have this combination.) In addition, it seems to make an error early on. Two minutes into her talk, Cuddy states that “Nalini Ambady, a researcher at Tufts University, shows that when people watch 30-second soundless clips of real physician-patient interactions, their judgments of the physician’s niceness predict whether or not that physician will be sued.” Which study is this? I have perused the Ambady Lab website, conducted searches, and consulted bibliographies—and I see no sign that the study exists. (If I find that the study does exist, I will post a correction here. Ambady died in 2013, so I cannot ask her directly. I have written to the lab but do not know whether anyone is checking the email.)

In separate studies, Ambady studied surgeons’ tone of voice (by analyzing subjects’ ratings of sound clips where the actual words were muffled) and teachers’ body language (by analyzing subjects’ ratings of soundless video clips). As far as I know, she did not conduct a study with soundless videos of physician-patient interactions. Even her overview articles do not mention such research. Nor did her study of surgeons’ tone of voice make inferences about the likelihood of future lawsuits. It only related tone of voice to existing lawsuit histories.

Anyone can make a mistake. On the TED stage, delivering your talk from memory before an enormous audience, you have a million opportunities to be fallible. This is understandable and forgivable. It is possible that Cuddy conflated the study of physicians’ tone of voice with the study of teachers’ body language. Why make a fuss over this? Well, if a newspaper article were to make such an error, and were anyone to point it out, the editors would subsequently issue a correction. No correction appears on the TED website. Moreover, many people have quoted Cuddy’s own mention of that study without looking into it. It has been taken as fact.

Why did I sense that something was off? First, I doubted that subjects’ responses to a surgeon’s body language predicted whether the doctor would be sued in the future. A lawsuit takes money, time, and energy; I would not sue even the gruffest surgeon unless I had good reason. In other words, the doctor’s personality would only have a secondary or tertiary influence on my decision to sue. On the other hand, it is plausible that doctors with existing lawsuit histories might appear less personable than others—if only because it’s stressful to be sued. Insofar as existing lawsuit histories predict future lawsuits, there might be a weak relation between a physician’s body language and his or her likelihood of being sued in the future. I suspect, though, that the data would be noisy.

Second, I doubted that there was any study involving videos of physician-patient interactions. Logistical and legal difficulties would stand in the way. With sound recordings—especially where the words are muffled—you can preserve anonymity and privacy; with videos you cannot. As it turns out, I was flat-out wrong; video recording of the doctor’s office has become commonplace, not only for research but for doctors’ own self-assessment.

It matters whether or not this study exists—not only because it has been taken as fact, but because it influences public gullibility. If you believe that a doctor’s body language actually predicts future lawsuits, then you might also believe that power pose effects are yours for the taking. You might believe that “the vast majority of teachers reports believing that the ideal student is an extrovert as opposed to an introvert” (Susan Cain) or that “the whole purpose of public education throughout the world is to produce university professors” (Ken Robinson). These hyperbolic statements weaken the authors’ otherwise compelling points. A TED talk is supposed to put forth a big idea–but any idea, no matter how large, benefits from challenge. Ideas and doubts go together; if you can’t question an idea–at any level, from any angle–it turns into dogma.

What to do? Questioning Cuddy’s statement, and statements like it, requires doubt and the ability to work with it. (Andrew King gives some excellent suggestions on how to think critically–in the true sense of the phrase–about scientific findings.) If TED were to open itself to doubt, uncertainty, and error—posting corrections, acknowledging errors, and inviting discussion—it could become a genuine intellectual forum. To help bring this about, people must do more than assume a doubting stance. Poses are just poses. Insight requires motion—from questions to investigations to hypotheses to more questions.  This is what makes science interesting and strong.

Update: TED has changed the title of Cuddy’s talk from “Your Body Language Shapes Who You Are” to “Your Body Language May Shape How You Are.” In addition, the talk’s page on the TED website has a “Criticism & updates” section, last updated in August 2017. Both are steps in the right direction.

Note: I made some revisions to this piece (in several stages) long after posting it.

What Does “Predict” Mean in Research?

In her TED talk, Amy Cuddy says,

Nalini Ambady, a researcher at Tufts University, shows that when people watch 30-second soundless clips of real physician-patient interactions, their judgments of the physician’s niceness predict whether or not that physician will be sued.

This is quoted all over the place, yet I have been unable to track down the study. Maybe it is unpublished or in press, or maybe it is published under a title that doesn’t mention physicians or videos.

In the meantime, I wonder whether Cuddy might have conflated two separate studies by Ambady: one of surgeons’ tone of voice (2002), and another of soundless clips of teachers (1993).

But my greater concern is with the word “predict.” As Cuddy puts it, the “judgments of a physicians’ niceness” actually predict whether or not that same physician will be sued in the future. To determine this, a researcher would have to follow the physicians over the long term and compare their subsequent lawsuit patterns (if any) to the initial ratings.

That would be terrifically difficult to accomplish. First, doctors with malpractice litigation histories are a small percentage of the whole, so the sample size would be tiny. Second, how long do you wait for a doctor to be sued? Two years? Five? Ten? Indefinitely?

Instead, I suspect the study followed a procedure similar to that of “Surgeons’ Tone of Voice.” (If I find out I am wrong, I will post a correction.) That is, the ratings of the videos were related to doctors’ existing lawsuit history. If there was any prediction, it was retrospective; as the authors state in the surgeon study, “Controlling for content, ratings of higher dominance and lower concern/anxiety in their voice tones significantly identified surgeons with previous claims compared with those who had no claims” (emphasis mine).

Why does this matter? There’s a big difference between predicting past and future events. People are easily dazzled by the idea that a thirty-second video clip (or sound clip, or whatever it may be) can predict a future lawsuit. The idea that it might predict a person’s existing history is perhaps interesting (if it holds up under scrutiny) but less dazzling.

When it comes to doctors, I imagine those with a lawsuit history might be a little grumpier than the others. I can also see how tone of voice could affect patients’ sense of trust and comfort. But I know of no study that demonstrates that ratings of soundless video clips of physicians predict whether they will one day be sued.

To avoid turning scientific research into a magic show, use the word “predict” carefully and precisely. Also, give a little more detail when referring to research, so that those interested can look up the study in question.

Update: I just learned that Ambady died in 2013. See the comments below. Thanks to Shravan Vasishth for the information.

Another update: Thanks to Martha Smith for explaining various  kinds of “prediction” in statistics. (See here and here.)