Strengths and limitations
familial BC/OC
MINOR
The study has limitations that are unavoidable due to the nature of the intervention: Since DA use was voluntary and actual using patterns were not collected, it cannot be guaranteed that all IG participants used the DA. Contamination in the CG cannot be excluded, because CG participants might have gained access to the DA unintentionally. Both DA non-use in the IG and unintentional DA use in the CG could influence response behavior and contribute to potential bias. It also remains unclear to what extent participants used other sources of information and support. These could help mitigate or amplify potential effects of the DAs. Another limitation could be the unequal age distribution in the IG and CG. To check for potential bias, all main outcomes were also examined for the age groups 18–40 years and > 40 years to make possible age-related differences transparent. These revealed only minor significant differences not related to the primary endpoint. It may also be considered a limitation performing a monocentric study at a single GC-HBOC center, which could limit representativeness of the results. However, the center at the University Hospital Cologne is the largest GC-HBOC center in Germany with a broad catchment area and the largest annual number of women seeking counseling for familial BC/OC risks. Thus, it can be assumed that a wide range of women with different attitudes, needs, and experiences were able to participate in the study. A strength of this study is the RCT design including a high number of participants, which means that results of high significance for clinical care can be expected. In addition, the study was conducted in the setting of usual care (current gold standard), which corresponds to the real care situation. Comparing “usual care without DA” and “usual care plus DA” allows a clear assessment of the additional benefit that DAs can provide in the current care concept.