Purpose of this Article
Conjoint analysis is a stated preference survey method that increasingly is being used in health and medicine as a means to identify and value aspects of both health and health care (1-2). Given that conjoint analysis is grounded in several disciplines, including psychology, economics, decision sciences and marketing, there exists an abundance of different techniques and approaches to the method (3). In health and medicine, conjoint analysis has become an umbrella term that spans several different methods. Applications in health and medicine often refer to discrete choice experiments, stated-preference methods, best-worst scaling and many other terms. While many of these terms are used correctly, the variety of terms often makes such applications difficult to identify in the literature and difficult for a general medical or outcomes research audience to interpret.
Despite the growing number of applications of conjoint analysis in health, the broad acceptance of conjoint analysis methods is hindered by the variation in methods, terminology, and quality of their applications in these fields (4). Furthermore, the lack of methodological standards for the application of conjoint analysis in health and medicine likely has slowed the pace of publication of conjoint analyses. Likewise, variation in peer review and editorial processes among scientific journals has resulted in wide variation in the quality of published conjoint studies.
The ISPOR Conjoint Analysis in Health Good Research Practices Task Force was established to identify good research practices in the application of conjoint analysis in health and medicine. It is important to note that the members of the Task Force, and the members of the Patient Reported Outcomes & Preferences Special Interest Group’s Patient Preference Methods (PPM) – Conjoint Analysis Working Group that oversee and initiated the agenda of the working group, agreed that the development of strict guidelines to conducting conjoint analysis in health and medicine was not possible for the following reasons:
One of the strengths of conjoint analysis is its flexibility, and the imposition of strict guidelines could limit its application.
Given the interdisciplinary nature of conjoint analysis, it would be unlikely that a consensus of best practices would be reached.
Many of the possible applications of conjoint analysis in health and medicine have been unexplored, underexplored, or under-published, so best practices would be difficult to establish during this current period of rapid methodological advancement.
As such, the Task Force endeavored to provide broad guidance on good research practices by offering some structure to the development, analysis, and publication of conjoint analyses in health. Therefore, this report deviates slightly from the traditional approach taken in ISPOR Task Force reports (5-7), in that it serves as part tutorial on conjoint analysis and part guidance on good research practices. The primary objective of this report is to present a checklist for identifying good research practices in the application of conjoint analysis in health and medicine suitable for researchers, peer reviewers, and users to improve the quality of published conjoint analyses
ISPOR Conjoint Analysis in Health Task Force Report