Can cognitive biases during consumer health information searches be reduced to improve decision making?

To test whether the anchoring and order cognitive biases experienced during search by consumers using information retrieval systems can be corrected to improve the accuracy of, and confidence in, answers to health-related questions.

A prospective study was conducted on 227 undergraduate students who used an online search engine developed by the authors to find health information and then answer six randomly assigned consumer health questions. The search engine was fitted with a baseline user interface and two modified interfaces specifically designed to debias anchoring or order effect. Each subject used all three user interfaces, answering two questions with each.

Frequencies of correct answers pre- and post- search and confidence in answers were collected. Time taken to search and then answer a question, the number of searches conducted and the number of links accessed in a search session were also recorded. User preferences for each interface were measured. Chi-square analyses tested for the presence of biases with each user interface. The Kolmogorov-Smirnov test checked for equality of distribution of the evidence analyzed for each user interface. The test for difference between proportions and the Wilcoxon signed ranks test were used when comparing interfaces.

Anchoring and order effects were present amongst subjects using the baseline search interface (anchoring: p < 0.001; order: p = 0.026). With use of the order debiasing interface, the initial order effect was no longer present (p = 0.34) but there was no significant improvement in decision accuracy (p = 0.23). While the anchoring effect persisted when using the anchor debiasing interface (p < 0.001), its use was associated with a 10.3% increase in subjects who had answered incorrectly pre-search, answering correctly post-search (p = 0.10). Subjects using either debiasing user interface conducted fewer searches and accessed more documents compared to baseline (p < 0.001). In addition, the majority of subjects preferred using a debiasing interface over baseline.

This study provides evidence that (i) debiasing strategies can be integrated into the user interface of a search engine; (ii) information interpretation behaviors can be to some extent debiased; and that (iii) attempts to debias information searching by consumers can influence their ability to answer health-related questions accurately, their confidence in these answers, as well as the strategies used to conduct searches and retrieve information.