Table 1:

Variables measured in the What Comes Next Cohort and variables available for future planned linkages

Category and source	Variables	Baseline	Follow-up
Demographic
Chart review	Ethnicity	✓
	Ashkenazi Jewish ancestry	✓
	No. of biological children	✓
Registered Persons Database	Age	✓	✓
	Vital status	✓	✓
	Urban v. rural neighbourhood	✓	✓
	Neighbourhood income quintile	✓	✓
Ontario Marginalization Database	Ontario Marginalization Index	✓	✓
IRCC	Immigration status	✓	✓
ORG–Deaths	Cause of death		✓
Comorbidities
CIHI-DAD, NACRS, OHIP, SDS	Aggregated Diagnosis Groups	✓	✓
Comorbidity-specific data sets^*	Asthma, hypertension, diabetes, rheumatoid arthritis, kidney disease, COPD, stroke, HIV, dementia	✓	✓
Genetic testing: chart review	Date of genetic counselling	✓
	Site of genetic counselling	✓
	Results of previous testing	✓
	Reason for testing	✓
	Date of testing	✓
	Site of testing	✓
	Test type	✓
	Test result	✓
Family cancer history: chart review	No. of first-degree maternal relatives with breast cancer	✓
	No. of second-degree maternal relatives with breast cancer	✓
	No. of first-degree maternal relatives with ovarian cancer	✓
	No. of second-degree maternal relatives with ovarian cancer	✓
	No. of first-degree paternal relatives with breast cancer	✓
	No. of second-degree paternal relatives with breast cancer	✓
	No. of first-degree paternal relatives with ovarian cancer	✓
	No. of second-degree paternal relatives with ovarian cancer	✓
Personal cancer history
Chart review	Type of cancer	✓
	Stage at diagnosis	✓
	Age at diagnosis	✓
Ontario Cancer Registry	Date of cancer diagnosis	✓	✓
	Morphologic type	✓	✓
	Histologic type	✓	✓
	Stage at diagnosis	✓	✓
Treating physicians: CPDB	Age	✓	✓
	Specialty	✓	✓
	Years in practice	✓	✓
Hospital: INST	Hospital no.	✓	✓
	Hospital setting (academic v. non-academic)	✓	✓
Hospital admissions:^* CIHI-DAD	Date of admission	✓	✓
	Reason for admission	✓	✓
	Length of stay	✓	✓
Emergency department visits:^* NACRS	Date of visit	✓	✓
	Reason for visit	✓	✓
Surgical history: OHIP, CIHI-DAD, SDS	Type of surgery	✓	✓
	Date of surgery	✓	✓
Breast or pelvic screening or diagnostic imaging: OHIP, OBSP	Date of imaging	✓	✓
	Date of biopsy	✓	✓
Radiation treatment:^* ALR, OHIP	Body region irradiated	✓	✓
	Dates of planning and treatment	✓	✓
	Course of treatment	✓	✓
	Dose per fraction	✓	✓
	Intent of treatment	✓	✓
Chemotherapy:^* ALR, NDFP	Date of treatment	✓	✓
	Line of therapy	✓	✓
	Intent of treatment	✓	✓
	Drug administered	✓	✓
	Dose administered	✓	✓

Note: ALR = cancer-related activity level reporting, CIHI = Canadian Institute for Health Information, COPD = chronic obstructive pulmonary disease; CPDB = Corporate Provider Database, DAD = Discharge Abstract Database, INST = Institution Information System, IRCC = Immigration, Refugees and Citizenship Canada Permanent Resident Database, NACRS = National Ambulatory Care Reporting System, NDFP = New Drug Funding Program, OBSP = Ontario Breast Screening Program, OHIP = Ontario Health Insurance Plan, ORG = Office of the Registrar General, SDS = same-day surgery.
↵* Requires linkages not yet performed but available for future studies.