Predictors of knowledge and knowledge gain after decision aid use among women with BRCA1/2 pathogenic variants.

To identify factors contributing to baseline knowledge in women with BRCA1/2 pathogenic variants (PVs) and knowledge gain after decision aid (DA) use. Women with PVs in BRCA1 or BRCA2 genes were randomly assigned to an intervention group (IG) receiving DAs or a control group (CG). Of the total sample, 417 completed the baseline survey and were included in this analysis. Two multiple regression analyses were conducted: baseline data on socio-demographic, medical, decision-related and psychological variables were used to identify predictors for (1) baseline knowledge within the total group and (2) knowledge gain within the IG after DA use three months post study inclusion. At baseline, higher education status, no breast cancer history, and lower decisional conflict related to higher knowledge within the total group. After DA use within the IG, higher baseline scores for decisional conflict predicted higher knowledge gain, and higher baseline scores for depression and intrusion predicted lower knowledge gain. This study identified predictors of baseline knowledge and knowledge gain after DA use in women with BRCA1/2 PVs. Awareness of facilitating and hindering factors on these women's knowledge can improve understanding of their health literacy and enable further targeted support interventions.