Reliability and Concurrent Validity of the SARC-F and Its Modified Versions: A Systematic Review and Meta-Analysis

Objectives: Sarcopenia, being prevalent in up to 40% of older adults, is associated with adverse health outcomes. The international sarcopenia guidelines recommend screening for sarcopenia using the SARCF. A previous meta-analysis (2017) reported poor validity of the SARC-F among community-dwelling older adults. Since then, modified SARC-F versions were developed and new sarcopenia definitions were published, including the SARC-F for case-finding. This systematic review and meta-analysis aimed to assess the reliability of the SARC-F and its concurrent validity to identify sarcopenia. Design: Systematic review and meta-analyses. Setting and Participants: Adults (all ages) from any study population. Methods: A systematic search was conducted in MEDLINE, EMBASE, Cochrane, and CINAHL (January 1, 2013, to April 6, 2020). Articles were included if they reported on the reliability and/or concurrent validity of the (modified) SARC-F. No restrictions were applied for sex, age, study population, or sarcopenia definition. Reliability measures included inter-rater reliability, test-retest reliability, and internal consistency. Meta-analyses were performed for concurrent validity. Results: The 29 included articles included 21,855 individuals (mean age of 63.3 +/- 14.6 years, 61.3% females) among community-dwelling (n =16), geriatric inpatient (n = 5), geriatric outpatient (n = 2), nursing home (n = 2), and long-term care (n = 1) populations. The SARC-F had good (2/4 articles) to excellent (2/4 articles) inter-rater reliability, moderate (1/6 articles) to good (5/6 articles) test-retest reliability, and low (4/8 articles) to high (4/8 articles) internal consistency. The SARC-F had low to moderate sensitivity (28.9%-55.3%) and moderate to high specificity (68.9%-88.9%) according to the European Working Group on Sarcopenia in Older People (EWGSOP; n = 13), revised EWGSOP definition (EWGSOP2; n = 6), Asian Working Group for Sarcopenia (AWGS; n = 13), Foundation for the National Institutes of Health (FNIH; n = 8), International Working Group on Sarcopenia (IWGS; n = 9), and Society on Sarcopenia, Cachexia and Wasting Disorders (n = 2). The SARC-CalF had low to moderate sensitivity (45.9%-57.2%) and high specificity (87.7%-91.3%) according to the EWGSOP (n = 5), AWGS (n = 4), FNIH (n = 3), and IWGS (n = 3). Conclusions and Implications: Despite the good reliability of the SARC-F, its low to moderate sensitivity and moderate to high specificity make it nonoptimal to use for sarcopenia screening. It is recommended to apply the diagnostic criteria for sarcopenia without screening. (c) 2021 The Authors. Published by Elsevier Inc. on behalf of AMDA -The Society for Post-Acute and Long-Term Care Medicine. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/).

Automated summary

This study evaluated the reliability and concurrent validity of SARC-F in identifying sarcopenia, finding that it is not optimal for sarcopenia screening due to its low to moderate sensitivity and moderate to high specificity. It is recommended to directly apply the diagnostic criteria for sarcopenia instead. The study included approximately 21,855 participants from varied populations.