Incongruence between women's survey- and interview-determined decision control preferences: A mixed methods study of decision-making in metastatic breast cancer.

Objective: Women with metastatic breast cancer face numerous, complex treatment and advance care planning (ACP) decisions. Our aim was to develop a better understanding of women with metastatic breast cancer's decision-making preferences overtime and relative to specific types of decisions.

Methods: Convergent, parallel mixed-methods study. Participants completed the Control Preferences Scale (CPS) and a semi-structured interview of decision-making experiences at enrollment (T1; n = 22) and when facing a decision or 3 months later (T2; n = 19). We categorized women's decision-making experience descriptions into one of the CPS decisional styles and compared them to their CPS response. We constructed an analytic grid that aligned the interview-determined treatment and ACP decisional preferences with the CPS categories at T1 and T2 and calculated Cohen's kappa coefficient and congruence percentages.

Results: Participants (n = 22) were White (100%), averaged 62 years, married (54%), retired (45%), and had a bachelor's degree (45%). Congruence between CPS response and interview-determined treatment preferences at T1 was 32% (kappa = 0.083) and 33% (kappa = 0.120) at T2. Congruence between CPS survey response and interview-determined ACP preferences at T1 was 22.7% (kappa =0.092) at T1 and 11% (kappa = 0.011) at T2.

Conclusions: Although women selected a "shared" treatment decision-making style using the CPS validated tool, when interviewed their descriptions generally reflected a passive process in which they followed the oncologists' treatment suggestions. Future research should explore whether the incongruence between stated and actual decision-making style is a function of misinterpreting the CPS choices or a true inconsistency that could lead to adverse consequences such as decisional regret.