DISCLOSING THE UNCERTAINTY OF PROGNOSTIC ESTIMATES IN BREAST CANCER: CURRENT PRACTICES AND PATIENTS' AWARENESS OF UNCERTAINTY

Purpose:

Treatment decision-making is often guided by evidence-based probabilities, which may be presented to patients during consultations. These probabilities are intrinsically imperfect, and embody different types of uncertainty: aleatory uncertainty arising from the unpredictability of future events, and epistemic uncertainty arising from limitations in the reliability and accuracy of probability estimates. Risk communication experts have recommended disclosing uncertainty. We examined whether uncertainty was discussed during consultations, and whether and how patients perceived uncertainty.

Method(s):

Consecutive consultations about adjuvant treatment between early-stage breast cancer patients and medical oncologists were audiotaped, transcribed, and coded. Patients were interviewed after the consultation to gain insight on their perceptions of uncertainty.

Result(s):

In total 198 patients were included by 27 oncologists. Uncertainty was disclosed in 49% (97/197) of consultations. In those 97 consultations 84 allusions to aleatory uncertainty and 23 allusions to epistemic uncertainty were made. Overall, the allusions to the precision of the probabilities were somewhat ambiguous. Interviewed patients mainly referred to aleatory uncertainty if not prompted about epistemic uncertainty. Yet, even when specifically asked about epistemic uncertainty, one in four utterances made referred to aleatory uncertainty. When talking about epistemic uncertainty many patients contradicted themselves. In addition, one in ten patients seemed not to realize that the probabilities communicated during the consultation are imperfect. 

Conclusion(s):

Uncertainty is conveyed in only half of the consultations. If uncertainty is communicated, oncologists mainly refer to aleatory uncertainty, which is also the type of uncertainty that most patients perceive and seem comfortable discussing. Given that it is increasingly common for clinicians to discuss probabilities with their patients, guidance on whether, and if so, how to best communicate uncertainty is urgently needed.