Assessing Preferences Regarding Healthcare Interventions that Involve Non-Health Outcomes: An Overview of Clinical Studies.

Decision making in healthcare often involves decision alternatives that vary on different dimensions in conflicting ways, such as health benefits and costs. In such cases, it is not always easy to identify the best option, as a trade-off has to be made. In preference studies, patients evaluate health states or healthcare strategies reflecting this trade-off. A focus that is restricted to only health outcomes in decision making may be too narrow. Patients also derive utility, or experience disutility, from healthcare processes themselves. A range of techniques is available for eliciting valuations of patients for these processes and other non-health outcomes. At present, it is unclear to what extent, and how, clinical evaluation studies have taken into account non-health outcomes. We performed a systematic review of trade-off and valuation studies to assess the extent to which valuations of process and non-health outcomes have actually been elicited from patients, in what specialty areas, and what techniques were used.We identified 567 articles that addressed patients' preferences involving non-health outcomes. The main therapeutic fields were oncology (17%), gynecology/obstetrics (11%), pulmonology (11%), cardiology (7%), gastroenterology (6%), and infectious diseases (6%). There was an absolute increase from the early 1980s (a handful of studies published each year) to recent years (almost 100 publications per year). We noticed a strong increase in elicitation techniques aimed at identification of determinants of patients' preferences.The number of studies addressing preferences for medical dilemmas involving non-health outcomes is steadily increasing and covers the whole spectrum of health-related interventions across all medical fields. A diversification in application fields as well as in research methods was observed, reflecting a lack of standardization. There is a need for methodological standards and evidence-based criteria to evaluate the methodological quality and clinical validity of studies that address preferences for dilemmas involving non-health outcomes.