SARC-F: A validation study with community-dwelling older Japanese adults

Aim: The SARC-F is a useful clinical index for sarcopenia screening; however, this measure has low sensitivity. Furthermore, this tool has never been validated on community-dwelling older Japanese adults. The goal of the present study was to validate a Japanese version of the SARC-F and confirm its suitability for Japanese samples. Methods: Participants were 734 community-dwelling older adults in the Itabashi Ward, Japan. Bioimpedance measures, walking speed, grip strength and instrumental activities of daily living (IADL) were measured. Sarcopenia was defined using the European Working Group on Sarcopenia in Older People, the Asian Working Group for Sarcopenia criteria and Japanese-adjusted Asian Working Group for Sarcopenia. SARC-F receiver operating characteristic curves for each sarcopenia measure were used to evaluate diagnostic accuracy. Physical functioning, IADL and sarcopenia screening tools were compared with the SARC-F. Results: A total of nine men (3.1%) and 15 women (3.4%) were classified into a SARC-F sarcopenia group. The sarcopenia group had lower physical functioning and Mini Sarcopenia Risk Assessment scores and higher frailty status than the control group. The Cronbach's alpha for the SARC-F was 0.610, suggesting insufficient internal consistency. SARC-F scores were related to physical functioning, IADL, and Mini Sarcopenia Risk Assessment scores. Receiver operating characteristic analyses of the SARC-F based on each criterion showed low sensitivity, but high specificity. Conclusions: The Japanese version of the SARC-F appears to be a useful index for reflecting physical functioning and IADL. However, it is necessary to further determine whether this tool is useful for detecting sarcopenia among community-dwelling older adults.