SWAG: Racial bias in pain perception

This week’s edition of Psych Wednesdays was written by Michael Kraus. It was originally published on Psych Your Mind on April 20, 2013.

Tom Brady is no stranger to pain (source)

Every Wednesday afternoon, I gather with a bunch of faculty and graduate students at the University of Illinois to discuss a journal article about social psychology, and to eat a snack. This blog post reflects the discussion we had during this week’s seminar affectionately called Social Wednesdays and Grub (SWAG).

This week in SWAG we read an article about racial biases in perceptions of others’ pain. The American medical field has a long history of racial bias (Note: I think if you switched the words “medical field” with almost any other field, the sentence would be factually accurate. For example, “mathematics field” or “psychology field” but not “magnetic field”). American blacks tend to be diagnosed less accurately by medical staff than whites, to receive less optimal health care, and to be cared for less intimately. The authors, led by Sophie Trawalter of the University of Virginia, wondered about the source of this racial bias. They reasoned that it might arise in part from a belief that low status groups experience less pain than other groups in society. Blacks and other traditionally low status groups in America are perceived as having overcome greater hardships throughout their lives. As a result of contending with, and overcoming these hardships, low status groups are perceived to experience less pain than their more advantaged counterparts—their tough circumstances have made them tougher. This racial bias in pain perception is theorized to underlie the black-white treatment gap in medicine.

The authors tested this pain perception bias in an interesting way: In the first study, the authors examined injury reports made by the NFL. Injury reports are the fixation of fantasy football armchair quarterbacks everywhere, and they are frustrating largely because there is a great deal of error in how different teams report injuries for specific players. Teams categorize players with increasing levels of play likelihood based on a reported injury—with players labeled as “probable” more likely to play than players labeled as “questionable” or “doubtful.” The severity of team reported injuries is surprisingly independent from whether a player actually plays the following week. The authors wondered if there exists racial bias in the errors in these NFL injury reports such that black players are reported as more probable than their white counterparts, despite having the same injury.

Examining injuries that ranged from lacerations, to knee injuries, to stingers the authors found evidence for race bias in NFL injury reports: Specifically, black players were categorized as more probable than their white counterparts despite having the same type of injury.

In the remaining experiments, the authors sought causal evidence that race influences pain perception bias. They presented participants with a number of black and white faces that were pretested to be rated as similar on a number of attributes (e.g., emotion expression), and then asked participants about how much pain the target in the photograph would experience during a list of physical injuries like “having a tooth pulled.” The authors found that black faces elicited perceptions of reduced pain relative to their white counterparts to the same physical injuries.

In the final experiment, the authors attempted to link this racial bias in pain perception to social status. Participants were asked to imagine a person in a photograph (manipulated to be either black or white) who was low status, equal status, or high status within one’s workplace, and then to judge that person’s pain experience for the same list of physical injuries. In this analysis, status captured all the variance in pain perception: Imagined low status targets were perceived to experience significantly less pain than high status targets, presumably because low status individuals have overcome more hardships throughout their lives, and are tougher as a result.

I think SWAG enjoyed reading this article. One of the nice things about it is that it attempts to do what is the main goal of social psychology in my view—examine a phenomenon like racial bias in medicine with the goal of uncovering the specific reason(s) why this bias occurs. Testing the phenomenon with actual NFL injury data that both real athletes and armchair athletes care about is another positive because it engages a real issue with implications for the health of real individuals. Race bias in NFL injury reporting could put some black NFL players at greater risk of sustaining worse injuries or exacerbating existing ones.

SWAG had some questions about the data analyses throughout the studies—for instance, it’s not clear how the researchers analyzed the NFL data (Note: Because the study was published in PLOS one and the journal allows post publication comments, I went ahead and asked the authors about providing more data analysis details. I hope this will generate a response!). Still, it was exciting work and we couldn’t help but think up a number of different experiments to follow those presented in the paper. The article made us all excited about social psychology… and donut holes… the jelly filled ones in particular.


Trawalter S, Hoffman KM, & Waytz A (2012). Racial bias in perceptions of others’ pain. PloS one, 7 (11) PMID: 23155390

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