Diagnostic accuracy of the SARC-F questionnaire in Argentine older adults

INTRODUCTION: The SARC-F questionnaire is a simple and widely used tool for sarcopenia screening in different clinical settings. However, its diagnostic performance may vary according to population characteristics and health care context, highlighting the need for local validation studies. The aim of this study was to assess the diagnostic accuracy of the SARC-F questionnaire for detecting sarcopenia among older adults attending primary health care centers in Argentina. MATERIALS AND METHODS: A cross-sectional diagnostic accuracy study was conducted in adults aged 60 years and older attending primary health care centers. The SARC-F questionnaire was administered face-to-face, and its performance was evaluated against a definition of sarcopenia based on handgrip strength and appendicular muscle mass measured by bioelectrical impedance analysis. Sensitivity, specificity, predictive values, likelihood ratios, and the area under the receiver operating characteristic (ROC) curve were calculated. Alternative cut-off points were also explored. RESULTS: A total of 142 participants were included, with a sarcopenia prevalence of 9%. Using the =4 cutoff point, SARC-F showed a sensitivity of 38% and a specificity of 89%, with a positive predictive value of 26% and a negative predictive value of 93%. The area under the ROC curve was 0.65. Lowering the cut-off point increased sensitivity at the expense of reduced specificity. CONCLUSION: In this population of older adults attending primary health care centers, the SARC-F questionnaire demonstrated high specificity and limited sensitivity for sarcopenia detection. These findings support its use as an initial screening tool within a broader clinical and functional assessment strategy.