Electronic Thesis and Dissertation Repository

Thesis Format

Integrated Article


Doctor of Philosophy


Health and Rehabilitation Sciences

Collaborative Specialization

Musculoskeletal Health Research


Dr. Dave Walton


As a pain researcher, in order to have a better understanding of pain, we should adopt a multidimensional view, such as the biopsychosocial (BPS) model and consider physical, psychological, and social elements altogether. The studies in this dissertation are part of the bigger project of SYMBIOME in which the aim is to help to create and develop a prognostic clinical phenotype in people post musculoskeletal (MSK) trauma. Chapter 2 presents a Confirmatory Factor Analysis (CFA) in order to assess the structural validity of the first section of the new Gender Pain and Expectation Scale (GPES). Our analysis indicated a 3-factor structure “Relationship-oriented,” “Emotive” and “Goal-oriented”. Its construct validity was also assessed. The subsequent study, chapter 3, explores the roles of sex-at-birth, GPES subscales and their interactions in explaining the variability of Brief Pain Inventory (BPI) Severity and Interference scores. It showed no sex differences in scores of BPI Pain Severity and BPI Pain Interference. GPES Relationship-oriented had a significant association with BPI pain severity (r=0.20) while GPES Emotive had a significant correlation with BPI Interference (r=0.24). Also, hierarchical multivariate linear regression suggested that GPES Emotive could partially explain the variances in pain-related interference. Chapter 4 presents correlations between sex-at-birth, hormones (Progesterone, DHEA-S, Estradiol, and Testosterone), GPES subscales and BPI scores. Also, as our second goal of this chapter, potential pathways between these variables have been tested through structural equation modelling. It has been shown that GPES Relationship-oriented had a significant correlation with progesterone (r=-0.21) and DHEA-S (r=-0.33), and GPES Emotive had a significant correlation with the DHEA-S (r=-0.20). The GPES Goal-oriented had a significant association with estradiol (r=-0.20). Our findings suggest that gender-related interpersonal-expressive characteristics could have mediator roles in relationships between sex-at-birth and pain, and also between the hormones and BPI pain ratings.

Summary for Lay Audience

Pain is a message, a beautifully designed communication between our cells and our brains. Pain is also a unique feeling influenced by different factors. Accordingly, meeting the needs of people suffering from pain requires access to different types of pain management that come with a profound social and financial burden. The most common treatment for pain in the world and especially in North America has been opioid prescription. Canada is the world’s 2nd-highest per capita user of opioids. It is currently estimated that pain costs Canadians annually about 60 billion dollars. Gender bias is one of the pathways by which inequalities in pain management adversely affect men’s and women’s health. To study pain effectively, we must consider psychosocial, biological and cultural factors. One area that remains understudied is the differences in pain experience and reporting between men and women. A better understanding of the effects of sex and gender on pain reporting and recovery is a critical step in this direction, but the mechanisms to explain this difference remain unknown. Are women more culturally conditioned to report pain while men are conditioned to suppress it? Or are there biological differences that influence the way pain is experienced? While sex-based research has recently increased especially in animals, the topic of socially constructed gender roles and how they interact with biological sex differences in humans remains underexplored. I am proposing a new model to look at both gender and biological variables together. I will look at the links between sex, hormones, gender-related characteristics, and pain reports. I expect these results will lead to encouraging further investigating for better and more approaches to sex-and gender-based pain research and management. This comprehensive approach could represent a new direction in the field of pain and recovery that could change the way that pain is managed and help curb the opioid crisis.