Psychometric Validation of the Diabetes Knowledge Test in Medicaid-Eligible Adults

Abstract

Objectives: Discrete choice experiments (DCEs) are used in outcomes research to elicit stated preferences and characterize decision-making processes. A DCE presents participants with scenarios describing the research object as a combination of levels of relevant attributes. Multiple-scenario DCEs (MS-DCE), present two or more scenarios side by side and ask for a choice between the scenarios, while single-scenario DCEs (SS-DCE) present one scenario at a time and require a choice for each scenario. This study aimed to explore the use of SS-DCEs in healthcare research. MethOds: A systematic literature search, combining terms for DCEs with broad healthcare terms, was conducted in Medline, Embase and PsycInfo (no date restriction). Publications were independently reviewed by two reviewers. Eligible studies presented discrete choices based on single scenarios constructed with varying levels of attributes, and addressed a healthcare topic. Information on rationale and study design were extracted from all included studies. Results: Our search identified 3308 studies, of which 29 presented 26 different SS-DCEs eligible for inclusion, and 697 presented MS-DCEs. Thirteen of the 26 SS-DCEs were published between 2011 and 2015. The most common topics were treatment or diagnostic interventions (n= 15), and healthcare settings and programs (n= 4). Decisions were made on behalf of a third party (e.g. physician for a hypothetical patient, or adult caregiver for a child) in 14 of the 26 studies. Three studies indicated using a SS-DCE rather than a MS-DCE design as it more accurately represented the decision situation being investigated, e.g. a physician seeing one patient at a time. cOnclusiOns: We have provided a comprehensive synthesis of studies employing the less familiar SS-DCE design. This synthesis will be valuable for researchers considering employing an SS-DCE and for developing methodological guidance for future research using SS-DCEs. Further work is needed to explore the economic theory underpinning the SS-DCE design.