Table 1.

Variable list

Variable	Scale	Source (question asked)
Outcomes
Colonoscopy use between   baseline and follow-up	Binomial: Yes/No	Follow-up ACCFR questionnaire   (“Since the date of your last interview (baseline), have you had a colonoscopy?”)
Colonoscopy use within two   years of follow-up	Binomial: Yes/No	Follow-up ACCFR questionnaire   (“Since the date of your last interview (baseline), have you had a colonoscopy?”   and “What was your age when you had your most recent (colonoscopy) test?”)
Smoking between baseline   and follow-up	Binomial: Yes/No	Follow-up ACCFR questionnaire   (“Since the date of your last interview (baseline), have you ever smoked a cigarette   a day for three months or longer?”)
Smoking at follow-up	Binomial: Yes/No	Follow-up ACCFR questionnaire   (“Do you currently smoke at least one cigarette a day?”)
Exposures
Carrier status	Binomial: Carrier/Non-carrier	Genetic testing results available at the ACCFR
Receiver status at follow-up	Binomial: Receiver/Non-receiver	Dates of genetic counseling sessions provided from the ACCFR-referred clinics and   available at the ACCFR against dates of the ACCFR questionnaire administration
		Records of previous receipts of genetic testing results from elsewhere before follow-up   or refusals to receive genetic testing results from the ACCFR-referred clinics
Previous cancer diagnosis at   follow-up	Binomial: Yes/No	Baseline ACCFR questionnaire   (“Has a doctor ever told you that you had cancer, leukemia, or a malignant   tumour?”)
		Follow-up ACCFR questionnaire   (“Since the date of your last interview (baseline), has a doctor told you that you had   any type of cancer, leukemia, or a malignant tumour?”)
		Pathology reports, hospital records, and cancer registries accessed by the ACCFR
Controls
Age	Continuous: Years	Baseline and follow-up ACCFR questionnaires   (“What is your age?”)
Sex	Binomial: Female/Male	Baseline ACCFR questionnaire   (“Are you male or female?”)
Marital status	Binomial: Married or common-law/Single	Baseline ACCFR questionnaire   (“Marital status?”)
Education	Categorical: Less than high school/High, vocational,   or training school/College, university, or more	Baseline ACCFR questionnaire:   (“What is the highest level of education that you have completed?”)
Degree of relatedness to   family probands	Categorical: Self or identical twin/1st/2nd/3rd/Higher   degree	Family information collected at enrollment into the ACCFR
Colonoscopy use before   baseline	Binomial: Yes/No	Baseline ACCFR questionnaire   (“Have you ever had a colonoscopy?”)
Colonoscopy use within two   years of baseline	Binomial: Yes/No	Baseline ACCFR questionnaire   (“Have you ever had a colonoscopy?” and “What was your age when you last had   this (colonoscopy) test?”)
Smoking before baseline	Binomial: Yes/No	Baseline ACCFR questionnaire   (“Have you ever smoked at least one cigarette a day for three months or longer?”)
Smoking at baseline	Binomial: Yes/No	Baseline ACCFR questionnaire   (“Do you currently smoke at least one cigarette a day?”)