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 SARC-F. 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.