Effectiveness and Invasiveness in Patient Medical Decision Aids

Abstract

This research tested the hypothesis that including anecdotal evidence impacts treatment choice by influencing the trade-off between effectiveness and invasiveness. In addition, the role of decision-making style was examined. Participants imagined making a decision between two treatment options for angina (chest pain). Bypass is more effective, but more invasive; balloon angioplasty is less effective, but less invasive. Participants received statistics about the effectiveness of the two treatments, testimonials, or both. They then indicated their choice between the two treatment options and rated the importance of the effectiveness and invasiveness of the treatment chosen to their decision. A subset of the participants also completed the Decision Making Styles Inventory (DMI) which describes individuals on three styles of decision-making: analytical, intuitive, and regret-based. Treatment choice was not shown to differ between experimental conditions. However, ratings of the importance of treatment invasiveness and effectiveness did explain a significant amount of the variance in treatment choice. Therefore, the trade-off between effectiveness and invasiveness appears to be an important source of individual differences in treatment choice. In addition, this research provides some evidence that individual differences in decision-making style play a role in the impact of anecdotal evidence on treatment choice.