Context Matters: Emotional Sensitivity to Probabilities and the Bias for Action in Cancer Treatment Decisions

Background Past studies have shown a commission bias for cancer treatment, a tendency to choose active treatment even when watchful waiting is less risky. This bias suggests motivations for action beyond mortality statistics, but recent evidence suggests that individuals differ in their emotional sensitivity to probabilities (ESP), the tendency to calibrate emotional reactions to probability. The current study aims to examine the role of ESP in the commission bias, specifically whether those higher in ESP are more likely to choose watchful waiting when risk probabilities align with that choice. Methods Participants (N = 1,055) read a scenario describing a hypothetical cancer diagnosis and chose between surgery and watchful waiting, with random assignment between versions where the mortality rate was either lower for surgery or for watchful waiting. We modeled choice using the Possibility Probability Questionnaire (PPQ), a measure of ESP, and several other individual differences in a logistic regression. Results We observed a commission bias as in past studies with most participants choosing surgery both when surgery was optimal (71%) and when watchful waiting was optimal (58%). An ESP x Condition interaction indicated that the predictive role of ESP depended on condition. Those higher in ESP were more likely to choose surgery when probabilities favored surgery, beta = 0.57, P < 0.001, but when probabilities favored watchful waiting, ESP had a near-zero relationship with choice, beta = 0.05, P < 0.99. Conclusions The role of ESP in decision making is context specific. Higher levels of ESP predict choosing action when that action is warranted but do not predict a shift away from surgery when watchful waiting offers better chances of survival. ESP does not overcome the commission bias.