Trust in deliberation: The consequences of deliberative decision strategies for medical decisions

Oblective:
Decision aids (DAs) play an increasingly critical role in supporting patients in making preference-sensitive treatment decisions. One largely untested assumption of DA design is that patients should be encouraged to deliberate carefully about their options after being informed of those options. The purpose of the present research is to test the impact of deliberative versus intuitive decision strategies in medical decision contexts.
Methods:
In 3 experiments, participants were randomly assigned to make a hypothetical medical decision either intuitively, or using various deliberative strategies. In Study 1, we predicted that deliberation would improve decision confidence while not changing decisions. In Study 2, our aim was to establish whether the observed increase in confidence was due to decision-making effort, confirmation bias, or both. In Study 3, it was predicted that deliberation would cause participants to become more confident in suboptimal decisions.
Results:
Across 3 studies, participants who deliberated felt better about their decisions and decision process, even when the decision was the same as what would have been chosen intuitively (Studies 1 and 2), and even when the decision was normatively bad (Study 3). Study 2 additionally indicated that participants' confidence was driven by confirmation bias rather than effort justification.
Conclusions:
Deliberative tasks may often fail to be an effective debiasing tool, and components of patient decision aids that ask patients to deliberate may serve to improve how patients feel without improving the quality of their decisions.