Peralta 2000.

Methods	Retrospective cohort study
Participants	Family history/risk ‐ CRRM 23 (36%) had at least one 1st degree relative with BC 19 (29%) had at least one 2nd degree relative with BC Comparison group 35 (19.5%) had at least one 1st degree relative with BC 47 (26.1%) had at least one 2nd degree relative with BC
Interventions	CRRM = 64 with primary BC Comparison group: primary BC and no CRRM = 82
Outcomes	BC incidence Disease‐free survival BC survival All‐cause survival
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Free of selection bias?	High risk	This study did not adjust for all major confounders.
Free of performance bias?	Low risk	Information on participants’ medial history was obtained from a computerized prospective database.
Free of detection bias?	High risk	Valid disease‐free survival estimates depend on participants in both groups getting assessed at the same fixed intervals. Therefore, we do not know the validity of these data as intervals were not mentioned.
Free of attrition bias?	Low risk	Mean follow‐up was 6.8 years (0.3‐23.6 years)