Polish version of SARC-F to assess sarcopenia in older adults: An examination of reliability and validity

INTRODUCTION: SARC-F is a quick questionnaire recommended as a screening tool for sarcopenia. The aim of the study was to translate, adapt, and validate the Polish version of the SARC-F for community-dwelling older adults in Poland. MATERIALS AND METHODS: We included 160 Polish volunteers aged ≥ 60 years (44% of men). The Polish version of SARC-F was adapted following standardized forward-backward translation procedure. SARC-F was validated against the six sets of diagnostic criteria as the reference standards [developed independently by European Working Group on Sarcopenia in Older People1 (EWGSOP1), European Working Group on Sarcopenia in Older People2 (EWGSOP2), Foundation for the National Institutes of Health (FNIH) Sarcopenia Project, Asia Working Group for Sarcopenia (AWGS), the International Working Group for Sarcopenia (IWGS), and Society on Sarcopenia, Cachexia and Wasting Disorders (SCWD)]. RESULTS: SARC-F score ≥ 4 points was observed in 18.8% of the study population. Cronbach’s alpha was 0.70. The sensitivity of SARC-F varied from 33.3% to 50.0% depending on the diagnostics criteria used, while the specificity was about 85%. Positive predictive value (PPV) was low (about 30%) for five out of six sets of the diagnostic criteria used (EWGSOP2, IWGS, AWGS, FNIH, and SCWD), while the negative predictive value (NPV) was generally high (>88%). The area under the ROC curves (AUC) was 0.652–0.728. SARC-F had the largest AUC against FNIH criteria (0.728), indicating a moderate diagnostic accuracy. Similar results were found for EWGSOP2 and IWGS criteria. The AUC values were below 0.7 for AWGS, SCWD, and EWGSOP1 criteria. CONCLUSION: Based on the results, the Polish version of SARC-F shows excellent reliability and good internal consistency. High specificity and high NPV make SARC-F a useful tool to rule-out sarcopenia with high accuracy in community-dwelling older adults, independently of the diagnostic criteria used.