Abstract
INTRODUCTION: A typical health preference study conducts a single discrete choice experiment (DCE). For example, a health valuation study may elicit preferences on an individual's health-related quality of life along five EQ-5D-5L attributes (Mobility, Self-care, Usual Activities, Pain/Discomfort, Anxiety/Depression). Using this protocol, researchers can conduct a dual-DCE survey (ie, with two different full-block DCEs completed sequentially). To demonstrate this protocol, we will conduct 12 dual-DCE surveys in two waves and estimate the effects of different scenarios and descriptive systems on main effects (ie, incremental differences in value between levels). METHODS AND ANALYSIS: Each of the two DCEs in a dual-DCE survey equates to a stand-alone health valuation study. To demonstrate this protocol, each is an EQ-5D-5L valuation study, including d-efficient blocks of 15 kaizen tasks and 5 paired comparisons. In wave 1 (six surveys, 1000 US adults each), the two DCEs will differ by scenario (1-year episodes ending in recovery or death or no duration/ending described). In wave 2 (six surveys, 200 US adults each), the two DCEs will include the same 5 EQ-5D-5L attributes but differ by the number of additional attributes related to cognition: none, one composite attribute (memory/concentration) and two component attributes (memory, concentration). For each DCE, we will estimate a conditional logit model and test for differences in value using cluster bootstrap techniques. We hypothesise that the values will differ by scenarios and systems. As secondary analyses, we assess the effects of sampling, scenario/system order and DCE order. ETHICS AND DISSEMINATION: The independent review board (IRB) at Advarra determined that this research project (Pro00080475; 11 July 2024) is exempt from IRB oversight based on the Department of Health and Human Services regulations found at 45 CFR 46.104(d)(2). Furthermore, the IRB determined that the project is not subject to requirements for continuing review. To disseminate our findings, we will prepare multiple manuscripts for publication in peer-reviewed journals and present highlights at scientific meetings, such as the EuroQol Plenary Meeting, International Academy of Health Preference Research and ISPOR.