Patients' preferences for quality-of-life aspects in sarcopenia: a best-worst scaling study.

PURPOSE: As information on patients' preferences regarding quality-of-life aspects in sarcopenia is lacking, this study aims to assess the relative importance of the 14 items of a QoL questionnaire designed for sarcopenia (the SF-SarQoL) using a best-worst scaling (BWS) survey. METHODS: Participants, aged 65 years or older and community dwelling, who previously participated in the SarcoPhAge study, received a BWS survey via the mail. An object case BWS was selected in which participants completed 12 choice tasks, picking the most and least important aspect from 4 out of 14 SF-SarQoL items for each task. Relative importance scores (RIS) were estimated using Hierarchical Bayes modelling. A cluster analysis was also conducted to investigate whether several profiles with regards to QoL preferences were present. RESULTS: A total of 163 participants were included, aged 75 (IQR: 73-81) years old, and mostly women (n = 107; 65.6%). Two items were found to be significantly more important than others: "feeling a reduction of physical capacity" (RIS = 11.26), and "having balance problems" (RIS = 11.09). The least important items were "experiencing difficulty carrying heavy objects" (RIS = 2.89), and "feeling a reduction in muscle mass" (RIS = 3.82). We found relatively weak evidence for the presence of two clusters. One cluster prioritized items related to falls where the second prioritized items related to feeling physically capable. CONCLUSION: Not all QoL aspects were equally important. The relative weight of each QoL aspect may be used to interpret QoL results obtained with the SF-SarQoL or to inform target outcomes in interventional studies.