Women's pain is considered less intense than men's, even if both are going through the same level of suffering, a new study has found.
Researchers in the United States asked 50 participants to watch various videos of male and female patients who suffered from shoulder pain perform a range of motion exercises using their injured and uninjured shoulders. Patients also self-reported their level of discomfort when moving their shoulder.
The patients' facial expressions were also analysed through the Facial Action Coding System (FACS), which is used to help describe all visually discernible facial movements. The researchers used these FACS values in a formula to give an objective score of the intensity of the patients' pain facial expressions.
Study participants were asked to gauge the amount of pain they thought the patients in the videos were going through on a scale from zero, labeled as "absolutely no pain", and 100, labeled as "worst pain possible".
In a second experiment, researchers replicated the first part of the study, but after participants watched the videos, they were asked to complete the Gender Role Expectation of Pain questionnaire. This measures gender-related stereotypes about pain sensitivity, the endurance of pain, and willingness to report pain.
Participants also shared how much medication and psychotherapy they would prescribe to each patient and which treatment they believed would be more effective for medical care.
Overall, the study found that female patients were perceived to be in less pain than the male patients who reported and showed the same intensity of pain. Additional analyses using participants' responses to the questionnaire about gender-related pain stereotypes meant researchers could say these perceptions were partially explained by these stereotypes.
"If the stereotype is to think women are more expressive than men, perhaps 'overly' expressive, then the tendency will be to discount women's pain behaviors," says Elizabeth Losin, co-author of the study and assistant professor of psychology and director of the Social and Cultural Neuroscience lab at the University of Miami.
"The flip side of this stereotype is that men are perceived to be stoic, so when a man makes an intense pain facial expression, you think, 'Oh my, he must be dying.'
"The result of this gender stereotype about pain expression is that each unit of increased pain expression from a man is thought to represent a higher increase in his pain experience than that same increase in pain expression by a woman."
Losin adds that psychotherapy was chosen as more effective than medication for a higher proportion of female patients compared to male patients. Additionally, the study found the gender of the participants did not influence pain estimation - both men and women interpreted women's pain to be less intense.
Losin says she hopes the research will help find and address more gender disparities in healthcare.
"I think one critical piece of information that could be conveyed in medical curricula is that people, even those with medical training in other studies, have been found to have consistent demographic biases in how they assess the pain of male and female patients and that these biases impact treatment decisions," Losin says.
"Critically, our results demonstrate that these gender biases are not necessarily accurate. Women are not necessarily more expressive than men, and thus their pain expression should not be discounted."