An RCT of a decision aid to support informed choices about taking aspirin to prevent colorectal cancer and other chronic diseases: a study protocol for the SITA (Should I Take Aspirin?) trial

Table 1 Participant timeline

	Recruitment	Enrolment	Allocation	Post-allocation
Timepoint**	-t₂	-t₁	0	0 months	1 month	6 months
Enrolment:
Eligibility screen	X
Baseline questionnaire		X
Informed consent		X
Allocation			X
Interventions:
Aspirin decision aid				X
General CRC prevention brochure				X
Assessments:
Subjective numeracy scale		X
Decisional conflict					X
Multidimensional measure of informed choice					X
Self-reported daily adherence to aspirin						X
Discussion about CRC prevention with GP (GP records)						X

ISSN: 1745-6215