Socioeconomic disparities in colorectal cancer diagnostic pathways and diagnostic interval

Awardee: Laura Davis

Graduate Program: PhD

Institution: McGill University

Supervisor(s): Alyson Mahar, Erin Strumpf

ARCC Program Area(s): Health Systems, Services, and Policy

Competition: 2020

Project Summary:

Overwhelming evidence shows that socioeconomic factors, such as income, play a powerful role in determining the health of individuals. Within the cancer system, socioeconomic factors influence screening, stage at diagnosis and cancer survival. Less is known about how socioeconomic factors affect initial access to the cancer system through diagnostic pathways. Diagnostic pathways represent the route a patient takes from initial presentation of symptoms or screening to diagnostic tests and the final cancer diagnosis. They are described by cancer agencies for each cancer type and are created using national and international practice guidelines. The diagnostic interval is the time between initial presentation of symptoms to the final diagnosis. A longer diagnostic interval has been shown to be associated with later stage at diagnosis, increased patient anxiety and potentially shorter survival. Policies and interventions, such as rapid diagnostic assessment programs, exist to clearly describe diagnostic pathways, shorten the diagnostic interval and improve cancer care. More research is needed to improve our understanding of how diagnostic pathways and intervals differ across patients experiencing different socioeconomic factors. This understanding would inform whether policies and interventions, such as rapid diagnostic assessment programs, are able to reduce those inequalities and improve cancer care.

Family doctors play an essential role in the diagnostic pathway as they are the gatekeepers to the cancer system. Having a consistent relationship with a family doctor has been shown to increase cancer screening and could facilitate quicker referral to specialists. A consistent family doctor is more likely to understand their patients’ health history and social situation, which could result in increased awareness of cancer symptoms and decreased time to diagnosis, however, little is known if having a consistent family doctor shortens the diagnostic interval.

This thesis will determine differences in socioeconomic status, diagnostic pathways and the diagnostic interval and understand if access to a consistent family doctor shortens the diagnostic interval for individuals experiencing socioeconomic deprivation. We will examine these relationships among colorectal cancer patients in Ontario using routinely collected data. Diagnostic pathways and intervals are modifiable factors at the system-level that policy makers can act upon to improve equitable access, quality of care, and health outcomes for cancer patients. The results from this thesis will inform policies and interventions addressing the diagnostic pathways and interval among individuals experiencing socioeconomic deprivation. We will lay the groundwork for future studies using routinely collected data to examine the impacts of such policies and interventions on other inequalities.