Assessing the utility of the decoy effect on biologic treatment preference

Abstract

Background: Many patients struggle with choosing and adhering to biologics. Psychological approaches (e.g. decoy effect) may impact patients' choices when selecting a biologic. Objective: Assess whether decoy options influence choice between injectable treatment options. Methods: Following IRB approval, 750 subjects >18 years were recruited through MTurk. Subjects were randomized in a 1:1:1 ratio into the following groups: 1) baseline comparison between a more effective, weekly injection and a less effective, every-three-month injection; 2) baseline with a decoy inferior to the weekly injection; 3) baseline with a decoy inferior to the every-three-month injection. Treatment preference was self-reported and compared using chi-square tests. Results: Sixty-six percent of subjects preferred the weekly injection versus 34% for the every-three-month injection (group 1). There was a 4% increase in the number of subjects who preferred the weekly injection (70%; group 2; P=0.34) and a 3% increase for the every-three-month injection (37%) when a decoy inferior to them was included (group 3; P=0.56). Conclusion: Psychological approaches can be used to enhance treatment initiation and adherence. However, the decoy effect did not appear to have a significant impact in this study. Patients' preferences for efficacy versus frequency of injection may be rather fixed.