Psychology Ph.D. Dissertations


Weight, discrimination, and performance: Using self-determination theory to explain workplace outcomes related to weight

Date of Award


Document Type


Degree Name

Doctor of Philosophy (Ph.D.)



First Advisor

Russell Matthews (Advisor)

Second Advisor

James Albert (Other)

Third Advisor

Scott Highhouse (Committee Member)

Fourth Advisor

Abby Braden (Committee Member)


Using self-determination theory as a guiding framework, I examined the cascading negative effects of weight on weight discrimination (as captured by reduced leader-member exchange), psychological need satisfaction, intrinsic motivation, and performance. Since performance is a multidimensional construct, three common dimensions of performance (task performance, organizational citizenship behavior, and counterproductive work behavior) were modeled to assess any differential effects of weight on the different dimensions of performance. Contrary to expectations, the results of the structural equation modeling indicated that the sample of dental hygienists did not experience weight discrimination (i.e., weight was not related to LMX) and that weight was neither directly nor indirectly related to performance. Results of the structural equation modeling also indicated that LMX was incrementally related to psychological need satisfaction (competence, relatedness, and autonomy), but that only autonomy was incrementally related to intrinsic motivation. Surprisingly, intrinsic motivation was not incrementally related to any performance measure. Furthermore, post-hoc analyses revealed that the sample of dental hygienists did not experience other, more overt, forms of weight discrimination (incivility), providing further support that this sample does not experience as much weight discrimination as samples in previous research. Additionally, post-hoc analyses revealed that the specific form of weight measurement (self-report BMI or self-report images) influenced effect sizes, such that BMI was significantly related to key variables (e.g., competence need satisfaction, task performance, CWB), while figural images were not. Implications, future directions, and limitations are also discussed.