Lee et al. 2020 (UK Biobank SMMI)
About this reference
Lee et al. (2020) derived sex-specific reference curves for skeletal muscle mass index (SMMI = appendicular skeletal muscle mass / height²) from 390,565 White adults in the UK Biobank. Muscle mass was measured by bioelectrical impedance analysis (BIA). The study published centile tables (C2, C25, C50, C75, C98) for each single year of age from 40 to 69. We use C2 as a proxy for P5, C25 as P25, C50 as P50, C75 as P75, and C98 as a proxy for P95. C2 and C98 are not exact equivalents of P5 and P95 — they are the nearest reported values and serve as approximations.
Known limitations
- BIA is less precise than DXA for measuring appendicular muscle mass; values may differ from DXA-based references like Kelly et al. 2009 (NHANES).
- The cohort is predominantly White British; values may not apply to South Asian, Black, or other ethnic groups.
- Volunteer recruitment via post may oversample healthier individuals (healthy-volunteer bias).
- Age range is restricted to 40-69; no data for younger or very old adults.