Table 2 Summary of variables to be assessed, examples and associated timeline
From: Prospective study of high-risk, BRCA1/2-mutation negative women: the ‘negative study’
Variable | Example | Baseline | Biennial follow-up | As needed/patient reported |
|---|---|---|---|---|
Information collected by research questionnaire | ||||
Reproductive factors | Age at menarche, parity, breastfeeding | X | X | |
Exogenous hormonal exposures | OC use, HRT use | X | X | |
Body size – current, at age 18, 30 and 40 | Weight, height | X | X | |
Lifestyle factors | Physical activity, smoking status | X | X | |
Screening | MRI, mammogram, breast biopsy | X | X | |
Surgery | Mastectomy, oophorectomy, other | X | X | |
Chemoprevention | Tamoxifen, raloxifene, etc. | X | X | |
Cancer diagnosis | Breast cancer, other cancers | X | X | X |
Family history | Any new cancer diagnoses | X | X | |
Updated contact information | Participant, alternate contact | X | X | X |
Information collected by DHQ | ||||
Queries frequency of intake over the past year for 124 individual food items and provides accurate estimates of usual daily dietary intake. | Linked to the Canadian Nutrient file, this database contains average values for the content of 112 nutrients in 4,943 foods available in Canada | X | X | |
Information collected from medical records | ||||
Mammographic density (% density) | Quantify density using Cumulus 4 software | X | ||
MRI | X | |||
Pathology for breast cancer diagnoses | Histology, stage, grade, hormone-receptor status, treatment regimens | X | ||
Information collected from biological samples | ||||
DNA | Sequencing for mutations in 23 genes in BrOCaP panel | X | X | |
Plasma | Sex hormone levels, nutrients | X | X | |
Toenail clippings | Selenium levels | X | X | |