Number of paired measurements (n) | Mean of paired measurements | Difference between first and second measurement Mean (95% CI) | P values | Technical error of measurement (CV) | |

Non-standers (n=30) | |||||

Impedance (Ω) | 22 | 878.9 | 0.05 (−34.7 to 34.8) | 0.99 | 54.1 (6.16) |

Fat-free mass index (kg/m^{2})* | 21 | 12.9 | 0.67 (5.25) | ||

Fat mass index (kg/m^{2})† | 21 | 6.46 | 0.8 (12.39) | ||

Standers (n=23) | |||||

Impedance (Ω) | 16 | 635.6 | 2.6 (−24.4 to 29.5) | 0.8 | 34.7 (5.45) |

Fat-free mass index (kg/m^{2})* | 16 | 16.41 | 0.53 (3.23) | ||

Fat mass index (kg/m^{2})† | 16 | 6.65 | 0.59 (8.93) |

Difference in means P value assessed by paired t-test. TEM=√∑d

^{2}⁄2 n, where d is difference between two measurements and n is no. of measurements. CV: %TEM=100xTEM/mean.*Calculated using the equations by Houtkooper

*et al*1: FFM=0.61×ht^{2}/impedance +(0.25xweight)+1.31. Fat-free mass index=fat free mass/supine length^{2}.13†Fat mass=body weight−fat-free mass. Fat mass index=fat mass/supine length

^{2}.13CV, coefficient of variability.