Table 3 Determinants of RFCSA
ModelCovariablesRegression coefficients (95% CI)p ValueModel r2
Healthy (n = 26)I(1) FFM6.0 (0.9 to 11.1)0.0240.59
(2) Sex (F − M)−120.2 (−214.1 to −26.3)0.014
COPD (n = 30)II(1) FFM2.4 (−1.7 to 6.5)0.2400.30
(2) Sex (F − M)−62.1 (−120.8 to −3.3)0.039
III(1) MRCDS−76.2 (−106.3 to −46.1)<0.0010.49
IV(1) FFM0.6 (−2.8 to 4.1)0.7080.55
(2) Sex (F − M)−36.9 (−87.1 to 31.2)0.142
(3) MRCDS−62.2 (−96.1 to −28.3)0.001
  • FFM, fat-free mass (in kg); RFCSA, rectus femoris cross-sectional area (in mm2); MRCDS, Medical Research Council dyspnoea score.

  • Results of regression analyses performed to investigate the relationship of FFM and sex with RFCSA in mm2. All regression models included a constant value. Regression coefficients describe the change in the RFCSA (as the dependent variable) per unit change of each covariable.