The influence of anchoring on pain judgment

Context. Research on decision making suggests that a wide range of spontaneous processes may influence medical judgment. Objectives. We considered an easily accessible strategy, anchoring and insufficient adjustment, which might contribute to the healthcare professionals’ miscalibration of patients’ pain. Methods. A sample (N = 423) of physicians, nurses, medical students and nursing students participated in a computerized task that showed sixteen vignettes featuring fictitious patients reporting headache. In the experimental condition, participants were asked to evaluate the severity of patient’s pain before and after knowing the patient’s rating. In the control condition, participants were shown all information about the patient at the same time and were required to make judgments in a single stage. Results. When participants could express an initial impression before knowing the patient’s rating, they fully anchored to their initial impressions in almost half of the responses. Moreover, even among those who revised the initial impression, the extent of the revision was often insufficient. Greater anchoring was associated with patients’ ratings which were higher than the participants’ initial impression. Finally, we provided evidence that anchoring increased pain miscalibration. We discuss our findings in terms of their contribution to the understanding of the cognitive processes involved in pain assessment. Conclusion. When estimating patients' pain intensity, observers are driven by anchoring, a rule of thumb that might have pernicious consequences in terms of unwarranted overreliance on initial impressions and insufficient revision in light of relevant disconfirming evidence. Taking into account this heuristic might foster accurate pain assessment and treatment.