Table 3 Reproducibility of bone mineral density measurements in the hands, right femoral neck and L2–4 spine
Mean both handsRight handRight femoral neckSpine L2-4
Baseline BMD (g/cm2), mean (SD)0.445 (0.055)0.454 (0.056)1.003 (0.146)1.299 (0.167)
Bland and Altman method0.0006 (−0.0006 to 0.0017)0.0003 (−0.0017 to 0.0010)0.0058 (−0.0055 to 0.0170)−0.0028 (−0.0153 to 0.0097)
Difference*, mean (95% CI)
SD difference†0.00510.00620.03890.0432
SDD‡+/−0.0101+/−0.0122+/−0.0762+/−0.0846
SDC§+/−0.0071+/−0.0086+/−0.0539+/−0.0598
CV (%)0.820.962.752.33
2√2CV (%)2.322.727.786.59
  • BMD, bone mineral density; CV, coefficient of variation; mean difference, mean of the difference between the first and the second BMD measurement; SDC, smallest detectable change (g/cm2); SDD, smallest detectable difference (g/cm2); SDdifference, SD of the difference between the first and the second BMD measurement.

  • *Systematic bias.

  • †Random measurement error.

  • ‡∼95% Limits of agreement between individuals (assuming no systematic bias).

  • §∼95% Limits of agreement within individuals (assuming no systematic bias).