Table 3 Reproducibility of bone mineral density measurements in the hands, right femoral neck and L2–4 spine.
| Mean both hands | Right hand | Right femoral neck | Spine 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 method | 0.0006 (−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† | 0.0051 | 0.0062 | 0.0389 | 0.0432 | ||||
| SDD‡ | +/−0.0101 | +/−0.0122 | +/−0.0762 | +/−0.0846 | ||||
| SDC§ | +/−0.0071 | +/−0.0086 | +/−0.0539 | +/−0.0598 | ||||
| CV (%) | 0.82 | 0.96 | 2.75 | 2.33 | ||||
| 2√2CV (%) | 2.32 | 2.72 | 7.78 | 6.59 |
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).