Comparison of Diagnostic Performance of SARC-F and Its Two Modified Versions (SARC-CalF and SARC-F+EBM) in Community-Dwelling Older Adults from Poland

Abstract

Purpose: Older adults should be routinely screened for sarcopenia, which threatens healthy, independent aging. The most popular screening tool is the SARC-F questionnaire. As its sensitivity is unsatisfactory, two modified versions of the questionnaire have been published: SARC-CalF (including calf circumference as an additional item) and SARC-F+EBM (assessing additionally age and Body Mass Index). The diagnostic performance of the three versions of the questionnaire has not been compared. The analysis aimed to assess the diagnostic value of SARC-F, SARC-CalF, and SARC-F+EBM questionnaires, and to compare their psychometric properties against two reference standards of sarcopenia diagnosis, ie, EWGSOP1 and modified EWGSOP2 criteria.

Materials and methods: We performed the sensitivity/specificity analysis and compared the overall diagnostic accuracy of SARC-F, SARC-CalF (31cm) (cut-off point 31 cm for both genders), SARC-CalF (33/34cm) (cut-off points: 33 cm for women and 34 cm for men), and SARC-F+EBM in 115 community-dwelling volunteers aged ≥ 65 yrs from Poland.

Results: Depending on the version of the SARC-F questionnaire used, from 10.4% [SARC-CalF (31cm)] to 33.0% (SARC-F+EBM) were identified as having an increased risk of sarcopenia. Sarcopenia was identified in 17.4% by the EWGSOP1 criteria and in 13.9% by the modified EWGSOP2 criteria. With respect to the two reference standards used, the sensitivity of SARC-F, SARC-CalF (31cm), SARC-CalF (33/34cm), and SARC-F+EBM ranged 30.0-37.5%, 35.0-37.5%, 60.0-62.5%, 55.0% (the same value for both reference standards), respectively. The specificity ranged 85.3-85.9%, 93.9-94.7%, 88.4-86.9%, 70.7-71.6%, respectively. The AUC of SARC-F, SARC-CalF (31cm), SARC-CalF (33/34cm) and SARC-F+EBM ranged 0.644-0.693, 0.737-0.783, 0.767-0.804, 0.714-0.715, respectively.

Conclusion: The modified versions of SARC-F have better diagnostic performance as compared to the original questionnaire. Since an ideal screening tool should have reasonably high sensitivity and specificity, and an AUC value above 0.7, the SARC-CalF (33/34cm) seems to be the best screening tool for sarcopenia in community-dwelling older adults.

Keywords: ROC analysis; SARC-F; older individuals; sarcopenia; screening.