Decision coaching for healthy women with BRCA1/2 pathogenic variants and open family planning: Impact on decisional conflict and decision status: Subgroup analyses from a randomized controlled trial.

Women with BRCA1/2 pathogenic variants (PVs) without a personal cancer history and with open family planning are in a very complex decision-making situation regarding their preventive and reproductive options. This exploratory study aims to assess the impact of a decision coaching (DC) program on decisional conflict and decision-making of these women regarding their preventive decision. BRCA1/2 PV carriers without a personal cancer history were recruited and randomly assigned to intervention or control group (IG, CG). The IG participated in a DC program consisting of in-person decision coaching and an evidence-based, structured decision aid about the preventive options (intensified breast surveillance, risk-reducing bilateral mastectomy, and risk-reducing bilateral salpingo-oophorectomy); the CG received usual care. Data was collected at baseline, 12 weeks and 6 months after study inclusion. Decision-related outcomes regarding the participants' preventive decision were measured with the Decisional Conflict Scale (DCS) and the Status of Decision-Making Scale. Subgroup analysis was performed to assess differences between women with open versus completed family planning using descriptive statistics and multiple linear regression models. Women with open family planning experienced higher baseline DCS scores regarding their preventive decision-making than women with completed family planning (mean DCS total score 39.5 vs. 34.4; mean difference -5.12, 95%CI [-9.328;-0.977], p = 0.018). In the total group, decisional conflict decreased considerably more in the IG than in the CG. Among women in the IG, those with open family planning showed a greater reduction in DCS scores than women with completed family planning. In initially undecided women with open family planning, 12 weeks after study inclusion significantly more women in the IG reached a preventive decision than in the CG (61.8% vs. 23.3%, p < 0.001). Significantly more women with open family planning in the IG opted for the intensified breast surveillance program compared to the CG. A DC program developed for unaffected BRCA1/2 PV carriers may contribute to reducing decisional conflict and increasing decision-making, especially in women with open family planning.