Investigations into screening mammography participation, retention and outcomes in British Columbia, Canada

Project number: 
16-080
Approval date: 
Thursday, September 22, 2016
Principal Investigator: 
Woods,Ryan
Institution: 
University of British Columbia (UBC)
Funding Agency: 
Not Available
Datasets requested: 
Income band (Statistics Canada)
Medical Services Plan (BC Ministry of Health)
consolidation - census geocodes
MSP Practitioner File
Deaths (BC Vital Statistics Agency)
Consolidation - demographic (Ministry of Health)
ACG Case Mix Group (Johns Hopkins University)
bc cancer-external
Citizenship and Immigration Canada (CIC) Permanent Residents
Consolidation registry (Ministry of Health)
Hospital Separations (BC Ministry of Health)
PharmaNet
Research objective: 

The questions for this research project are:

1) a) What is the fraction of currently eligible women who have ever participated in programmatic breast screening in BC?
b) What are the characteristics of eligible women who participated in mammography once in the past, but never returned?
c) How do these compare to the characteristics of women that have never participated in SMPBC?

2) Are primary care physicians (PCP) factors (practice style other characteristics) and/or patient factors (recent immigration, country/region of origin) associated with breast screening participation?

3) Are PCP factors (practice style, other characteristics) and/or patient factors (recent immigration, country/region of origin associated with screening program retention?

4) Are PCP factors (practice style, other characteristics) and/or patient factors (recent immigration, country/region of origin associated with a delay of uptake into mammography from the time women are first eligible for program participation in BC?

5) Are PCP factors (practice style, other characteristics) and/or patient factors (recent immigration, country/region of origin associated with time to receipt of follow-up investigations following abnormal mammogram results?

6) Does breast cancer stage at diagnosis vary by immigrant subpopulations and across levels of PCP practice style?

Hypotheses:

Although some of the analyses are descriptive in nature aiming to identify factors associated with screening endpoints and estimate screening indicators for various subgroups, we have some general hypotheses within this work:

1) a) Participation for certain immigrant sub-populations will be lower than for Canadian-born women. Based on previous studies in other jurisdictions, we hypothesize that several sub-populations of immigrant women (such as South Asian and Chinese women) will screen less than Canadian-born counterparts. Based on what has been observed in other regions around the general participation indicator, we hypothesize:
1b) retention of women from some immigrant subpopulations will be lower than for Canadian-born women
1c) women who migrate into BC experience a significant delay into uptake into mammography and miss screening over a significant portion of the recommended age range for screening

2) A significant fraction of eligible age women in BC will access primary care from PCP's whose practices align with lower levels of responsibility for ongoing management of patients they see.

3) Women who access primary care through PCP's whose practice style is characterized as lower levels of responsibility for ongoing management of patients they see will:
- Participate less in breast screening (compared to those who access care from "high responsibility" PCP's).
- Demonstrate lower retention (compared to those who access care from "high responsibility" PCP's).
- Start breast screening later than guidelines recommend and later than women who access care from "high responsibility" PCP's.

4) Stage distribution for women who are under-screened is worse than for those who attend screening. Because of this some sub-populations who are under-screened may associate with a late-stage presentation, even when tumour biology is considered.


Page last revised: December 5, 2017