Development and psychometric evaluation of a pre-sarcopenia risk assessment scale for sedentary young adults with type 2 diabetes mellitus

Aims The aim of this study was to develop a self-reported risk-assessment scale for pre-sarcopenia-related behavioral and functional risk in sedentary young adults with type 2 diabetes mellitus (T2DM) and to assess its psychometric properties. Methods Following COSMIN guidelines, an initial item pool was generated via literature review and semi-structured interviews, then refined through two Delphi rounds and a pilot survey. A convenience sample of 435 patients (June 2024–February 2025) was recruited; 215 participated in exploratory factor analysis (EFA) and 220 in confirmatory factor analysis (CFA). Reliability and validity were evaluated. Results The final 18-item scale comprises four dimensions: behavioral risk perception, muscle function monitoring, sedentary behavior characteristics, and intervention intention. EFA extracted four factors explaining 81.25% of the total variance. CFA demonstrated good model fit ( χ 2 /df = 1.583, RMSEA = 0.076, SRMR = 0.038, CFI = 0.965, GFI = 0.917). The scale-level content validity index was 0.92; Cronbach’s α was 0.894 and split-half reliability 0.792. Conclusion The newly developed scale showed satisfactory preliminary reliability and construct validity. It should be regarded as a self-reported risk-assessment instrument for pre-sarcopenia-related behavioral and functional risk, rather than a diagnostic or case-finding tool for pre-sarcopenia. Positive risk identification should be confirmed by objective measures such as handgrip strength, muscle mass, and physical performance.