Decision Coaching for Healthy Women With BRCA1/2 Pathogenic Variants

Findings of the Randomized Controlled EDCP-BRCA Trial

Background: Women with pathogenic variants (PV) of the genes BRCA1/2 have a choice of preventive options. To help these women decide for themselves, we developed and implemented a decision coaching (DC) program and evaluated it for congruence between the participants’ desired and actual roles in decision-making.

Methods: Healthy BRCA1/2 PV carriers (25–60 years of age) were recruited at six centers in Germany. Those who returned baseline (T1) questionnaires were randomly assigned to the intervention group (IG) or the control group (CG). The IG attended a nurse-led DC program. The primary outcome was congruence between the participants’ preferred and actual roles in decision-making. The secondary outcomes were an active role, satisfaction, decisional conflict, and knowledge. The follow-up questionnaires were administered at 12 weeks (T2) and 6 months (T3).

Results: Of the 413 women who were recruited, 389 returned the T1 questionnaires. At T2, the groups did not differ significantly in congruence between their preferred and actual roles in decision-making (0.12, 95% confidence interval [−0.03; 0.28], p = 0.128), with a slightly higher congruence in the CG. Women in both groups played a more active role at T2 than their stated preference at T1, with a notably higher percentage in the IG than the CG (IG: 40%, CG: 24.4% [−25.1; −6.1]). IG participants were more satisfied with their role and had less decisional conflict and greater knowledge.

Conclusion: This DC program can help women who are carriers of BRCA1/2 PV participate actively in decision-making with regard to preventive measures.

Women with pathogenic variants (PV) in the BRCA1/2 genes are at high risk for breast cancer (BC) and/or ovarian cancer (OC) (1, 2, 3, 4). Preventive options include intensified breast surveillance (IBS) and risk-reducing operations. IBS programs detect BC at an early, potentially curable stage in over 80% of cases (5). Risk-reducing surgeries include:

• Bilateral mastectomy (RRBM); this is associated with risk reduction to approximately 5% with a potential survival benefit for BRCA1 PV carriers (6, 7, 8).
• Bilateral salpingo-oophorectomy (RRBSO); this is associated with reduction of the OC risk to around 2% and lowers both OC-specific and overall mortality (9, 10, 11).

Unwanted consequences of RRBM may include problems regarding body image, feelings of femininity, and sexuality. RRBSO leads to fertility loss and may cause premature menopause. All options differ in their benefit–harm profiles and need to be weighed against each other, considering personal preferences and values.

To support the women in their complex decision-making process, improve their understanding of the available options, and help them to reflect on their preferences and personal circumstances, evidence-based decision aids (DA) and decision coaching (DC) can be used. DA can increase knowledge, reduce decisional conflict (especially that due to feeling uninformed), help clarify values and preferences, foster realistic appreciation of the risks, and facilitate informed decision-making (12). DC or DC plus DA may increase both knowledge and active participation in decision-making (13, 14). To date, however, there have been no randomized controlled trials (RCTs) among carriers of BRCA1/2 PV. DA and DC are not intended to replace patient–physician interaction but rather to enhance exchange and help patients take an active role in decision-making. Around 60–70% of patients state they want to take an active or shared role in decision-making (15, 16), but there is often a discrepancy with their perception of their actual role in the decision-making process (16). DC could be a valuable means of encouraging active participation in decision-making and thus supporting congruence between desired and actual role. In the present study, a structured, systematic decision-support program for women with BRCA1/2 PV consisting of a nurse-led DC and an evidence-based DA was developed, implemented, and evaluated in a multicenter RCT.

Methods

The trial has been registered prospectively (WHO primary register DRKS-ID: DRKS00015527) and a detailed study protocol has been published (17). The study is reported in accordance with the Consolidated Standards of Reporting Trials (CONSORT) (18).

Study implementation

Before the study commenced, the participating nurses were trained in DC using an adapted, evaluated curriculum (19, 20); the participating physicians were schooled in communication techniques based on the KoMPASS training (21).

The study included women aged 25–60 years with BRCA1/2 PV but without a BC/OC diagnosis who had a good knowledge of German and had not yet finally decided on their prevention strategy or given informed consent. The women were recruited at six centers of the German Consortium for Hereditary Breast and Ovarian Cancer (17), either during counseling with a physician after genetic testing or at a regular IBS visit. They received the baseline questionnaires after giving written consent. After returning the questionnaires, the women were randomized in a 1:1 ratio to the intervention group (IG) or the control group (CG). Randomization was stratified by center. Staff at the respective center were informed about each participant’s group allocation via encrypted email.

The intervention consisted of:

• A nurse-led DC comprising one or two sessions, using fact sheets, a decision guidance document
• An evidence-based DA (22, 23, 24)

The women in the IG were contacted by staff to arrange the first DC appointment. They received confirmation of the appointment date by mail, together with the DA. DC was usually provided face to face. During the COVID-19 pandemic, online DC was implemented. Women in the CG received regular care. All participants were counseled by trained physicians and had the opportunity to consult their physician again before coming to a decision.

The study hypothesis was that women who took part in the DC program would have closer congruence between preferred and actual role than women without this intervention (13, 25).

The primary outcome was therefore congruence between preferred role at baseline (T1) and actual role in the decision-making process 12 weeks after study inclusion (T2), measured using the Control Preferences Scale (CPS) (26). The CPS evaluates how actively a person wishes to participate in decision-making with five possible responses from active through collaborative to passive. Our choice of the CPS was based on the following assumptions:

• A large number of women confronted with oncological conditions desire an active role in the decision-making process (27).
• DC supports women who prefer an active role in decision-making to actually take such a role.
• Concordance of the role taken with the desired role results in better decision-related outcomes (25).

To determine congruence, the difference of T2 minus T1 was calculated for each participant. The closer the value to 0, the higher the congruence. A difference = 0 means perfect congruence, a difference < 0 means that the participant has taken a more active role than desired, and a difference > 0 means that the participant has taken a more passive role than desired.

The CPS was also used to determine activity levels at T1 and T2 as a secondary outcome. The other secondary outcomes were: satisfaction with the role taken in decision-making, decisional conflict, knowledge, decision status, self-reported mental symptoms (anxiety, depression, burden of genetic test result). More detailed information can be found in the eMethods. The measurements took place at baseline (T1) and at 12 weeks (T2) and 6 months (T3) after study inclusion. The eFigure shows the measurement sequence.

eFigure

Timeline for data collection

Sample

The assumptions for sample size calculation were: moderate effect size (Cohen’s d = 0.3), power of 0.8, α-level of 0.05, and a 30% dropout rate. Employing a two-sided t-test to gauge the mean difference in congruence between IG and CG, the calculated sample size is n = 504 participants. G*Power was used for the calculations (28).

Statistical analysis

The per-protocol analysis was accompanied by a sensitivity analysis in the form of an intention-to-treat analysis in which missing values were imputed using multiple imputation bychained equations (MICE). Metric variables were expressed as mean and standard deviation, categorical data as absolute and relative frequencies. The primary outcome was assessed by means of a two-sided t-test, with the results expressed in terms of 95% confidence interval [95% CI] and p-value. In light of the ordinal nature of the CPS, an ordinal regression was conducted as an additional sensitivity analysis, with the group variable as independent variable and the difference in CPS between T2 and T1 as outcome variable, adjusting for characteristics and CPS at baseline. Metric and categorical variables were compared by calculating differences in means or proportions together with the corresponding 95% CIs. The latter were ascertained by means of bootstrapping to account for parameter uncertainty. An α-level of 0.05 was considered significant. All analyses were conducted using IBM® SPSS® Statistics for Windows, version 29.0 (Armonk, NY, USA; IBM Corp.) and R (29).

Results

Twelve nurses completed the DC training, while ten physicians took part in the communication training.

A total of 413 BRCA1/2 PV carriers were recruited from 18 November 2019 to 27 October 2021. Figure 1 presents the study flow. Table 1 shows the basic characteristics of the study population and the numbers of participants from each study center. The profiles of the IG and the CG were comparable for all variables. Of note are the young mean age and the high proportion of participants with a university degree in both groups.

Figure 1

Study flow

Table 1

Characteristics and study centers

Congruence between preferred and actual role (primary CPS outcome)

In both groups, the mean CPS difference of T2 minus T1 was < 0 (IG −0.30 ± 0.66, CG −0.18 ± 0.75; 95% CI for the difference of 0.12: [−0.03; 0.28]; p = 0.128). This means that women in both the IG and the CG took a more active role at T2 than had been desired at T1. Congruence between preferred role at T1 and actual role at T2 was lower in the IG. The results were confirmed by ordinal regression (eTable 1).

eTable 1a

Primary analysis of intervention effect on trend in CPS

eTable 1b

Multiple ordinal regression on analysis of intervention effect on trend in CPS

Active role (secondary CPS outcome) and satisfaction with role taken

Figure 2 shows for the IG and the CG the shifts from the five activity roles desired at T1 to the roles actually assumed at T2. Included were all participants with data available at both T1 and T2. Overall, the majority of women in both groups preferred an active–collaborative role at T1 (IG: n = 134, 78.8%; CG: n = 136, 77.3%). At T2, the proportion of women who took on an active role was almost twice as high in the IG (n = 68, 40%) as in the CG (n = 43, 24.4% [−25.1; −6.1]). Details can be found in eTable 2.

eTable 2

Control preferences (using CPS)

Figure 2

Shift in activity roles in decision-making from T1 to T2 for IG and CG

With regard to the subgroups, the IG displayed a shift towards a more active role at T2 than had been desired at T1. Of those IG women who wished an active role at T1, 81% actually assumed an active role. Of those preferring an active–collaborative role, 36.6% moved to an active role and 59% remained active–collaborative. In contrast, the women of the CG tended to remain in an active–collaborative or collaborative role at T2 or even switched to such a role from an active role. For example, of the CG women who preferred an active role, 57.1% switched to an active–collaborative role and 35.7% remained in the active role. Of those desiring an active–collaborative role, 64.7% actually took such a role, while 9.6% moved to a collaborative and 25% to an active role.

Satisfaction with the role taken at T2 was higher in the IG than in the CG (3.47 vs. 3.20 [−0.45; −0.10]). (eTable 3).

eTable 3

Control Preferences Scale (CPS)

Secondary outcomes

Table 2 displays the results of the other secondary outcomes. At T1, all variables were comparable between the IG and the CG. At T2 and T3, decisional conflict and knowledge had improved in the IG compared with the CG, and more women in the IG had made their decision. eTable 4 shows which options were chosen by those who made their decisions. Regarding psychometric variables, anxiety levels were slightly lower at T2 and T3 in both groups, with the effect somewhat more apparent in the IG.

Table 2

Secondary outcomes without imputation of missing values

eTable 4

Decision in favor of preventive options

All analyses with imputed data showed only marginal deviations (eSupplement).

Discussion

In this study, a nurse-led DC program for women with BRCA1/2 PV was designed, implemented, and evaluated. Literature data indicate that:

• Decision support increases patients’ participation in decision-making.
• Women with BC have a higher than average level of preference for an active or active–collaborative role.

In a systematic review, around one third of patients report discrepancy between the preferred role and the role actually played in the decision-making process (16). In practice, variations from a desired shared role occur in both directions, to a more active or a more passive role. However, most studies on role preferences in BC patients used a cross-sectional design, notwithstanding the fact that patients’ preferences may change during the decision-making process. Moreover, preferences may be recalled incorrectly at a later date. Longitudinal studies to explore patients’ preferences and perceptions are needed to depict the evolution of preferences prospectively over time. The principal barriers to active involvement in decision-making are reported as lack of awareness of the choices on the part of the patient, lacking or inadequate clarification of the patient’s values and preferences by the physician (30, 31, 32, 33), and shortage of time during the consultation and the presentation of the evidence on the available options (34).

In concordance with the literature, the majority of women in our study desired an active–collaborative approach at T1. At T2, there was no significant difference between groups regarding the primary outcome: “congruence of desired and actually taken role in the decision-making process”. The study hypothesis could therefore not be corroborated. Instead, women in both groups reported having played a more active role at T2 than desired at T1, with an active role being played by a larger proportion of women in the IG. Congruence as main outcome was thus lower in the IG than in the CG. Possible explanations for the higher activation of the IG women are factors such as:

• A better understanding of the evidence base, benefits, and harms of the options
• Having more time to explore questions and consider facts relevant to the decision
• Consideration of personal values and preferences

With regard to the subgroups, women in the IG who preferred an active role at T1 displayed higher congruence with their actual role at T2 than those in the CG. In the subgroups preferring an active–collaborative role at T1, there was a tendency for more women in the IG than in the CG to switch to an active role at T2. Thus, the DC program may have motivated and supported the BRCA1/2 PV carriers in the IG to play a more active role in decision-making. This was the case both in the subgroup of women who preferred an active role at T1 and in the subgroup who preferred an active–collaborative role at T1. This is underlined by the finding that the women of the IG were more satisfied with their actual role than were those in the CG. Other factors associated with the desire for a more active role, such as age and a higher education level, were comparable in the IG and CG in our sample. In interpreting these results, it should be considered that not all women want to play an active role and that it is the aim of a DC to be non-directive regarding both the options and the desired role in decision-making.

Regarding the secondary outcomes, the level of knowledge was higher in the IG than in the CG throughout the study period. Moreover, due to the high education level of the sample, a ceiling effect was observed for both groups. Decisional conflict decreased in both groups, but the scores remained almost twice as high in the CG as in the IG. Also, the women of the IG reached a clear decision more often and earlier than those of the CG. This indicates that the IG women were more decisive, better prepared, and faster in the decision-making process. With regard to mental outcomes, anxiety decreased slightly more in the IG than in the CG, which could be due to the women of the IG reaching their decision earlier.

Strengths and limitations

One strength of the study is its relatively high internal and external validity, due to its design and implementation. This suggests good validity and good transferability to clinical practice. Since the DC could also be implemented online, widespread use in routine care seems feasible. Limitations arise from the high education level of the sample compared with the general population, which may have resulted from selection bias, and from the fact that women were recruited either during post-test genetic counseling by a physician or at a regular IBS visit, based on the hypothesis that these two groups are at similar stages of decision-making.

Further authors

Marcus Redaèlli, Birte Berger-Höger, Nicola Dikow, Marion Kiechle, Juliane Köberlein-Neu, Cornelia Meisel, Rita Schmutzler, Anke Steckelberg, Marion Tina van Mackelenbergh, Frank Vitinius, Achim Wöckel

Affiliations of the further authors

Conflict of interest statement
The authors declare that no conflict of interest exists.

Manuscript received on 19 October 2023, revised version accepted on 27 February 2024.

Corresponding author
Dipl.-Math. Arim Shukri
Universität zu Köln, Medizinische Fakultät und Uniklinik Köln,
Institut für Gesundheitsökonomie und Klinische Epidemiologie
Gleueler Str. 176–178
50935 Köln, Germany

Cite this as:
Stock S, Isselhard A, Shukri A, Kautz-Freimuth S, Redaèlli M, Berger-Höger B, Dikow N, Kiechle M, Köberlein-Neu J, Meisel C, Schmutzler R, Steckelberg A, van Mackelenbergh MT, Vitinius F, Wöckel A, Rhiem K: Decision coaching for healthy women with BRCA1/2 pathogenic variants—findings of the randomized controlled EDCP-BRCA trial. Dtsch Arztebl Int 2024; 121: 393–400. DOI: 10.3238/arztebl.m2024.0049

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