Born and raised in Hamilton, Shirley received her nursing diploma from Mohawk College and in early 1993 began working at the Hamilton Health Sciences. After working as a charge triage nurse in the Emergency Department and the operating room she moved into the area of clinical research full-time in 2005. Shirley coordinated the VISION Study, an international 40,000 patient observational cohort before becoming an Associate Program Manager at Population Health Research Institute.