A new study finds Americans take the pain of girls less seriously than that of boys

A student at Carlin Springs Elementary School in Virginia receives an H1N1 flu vaccination.

(CNN)Our long-held notions of boys as being more stoic and girls as being more expressive may lead Americans to overrate the severity of male physical pain.

A recent study by psychologists at Yale University found that adults, when presented with imagery of a child's finger being pricked, considered the child to be in less pain when they thought it was a girl.
The study, published in The Journal of Pediatric Psychology, involved showing 264 adult participants a video of a child whose gender appeared ambiguous. Afterwards one group of participants was told the child in the video was named Samuel, while the other group was told her name was Samantha. They were then asked to rate how much pain the "boy" or "girl" experienced against how much pain he or she displayed.
Participants rated the child as experiencing more pain when it was described as a boy.
    "Explicit gender stereotypes -- for example, that boys are more stoic or girls are more emotive -- may bias adult assessment of children's pain," the authors concluded.
    The study built on the work of one of its co-authors, Lindsey Cohen of Georgia State University, who led a 2014 study in Children's Health Care in which participants also rated their perceptions of a child's pain after watching a video of his or her finger being pricked. While that study used a predominantly female cohort of university-age students, the Yale study broadens that research, showing that the effect is measurable in a participant group of adults ages 18 to 75 and balanced between gender.
    Of particular note, said the Yale study's lead author, Brian Earp, is that the phenomena illustrated in the study primarily applies to female observers. While men were likely to rate perceptions of boys' and girls' pain more closely together, the women in the study felt boys' pain to be more acute than girls'.
    Earp said it was as though they thought, "'For a boy to express that much pain, he must really be in pain.'"