Table 2.
Reproducibility of fully automated vBMDL1-4 measurements in each group
| Group name | Group size | Measurement 1 vBMDL1-4 [mg CaHA/cm3] | Measurement 2 vBMDL1-4 [mg CaHA/cm3] | Absolute difference [mg CaHA/cm3] | Relative difference [%] | RMSE [mg CaHA/cm3] | RMSCV [%] |
|---|---|---|---|---|---|---|---|
| Number | Mean ± standard deviation | Mean ± standard deviation | Mean ± standard deviation | Mean ± standard deviation | |||
| Δrecona | 169 | 175.3 ± 54.8 | 175.4 ± 54.7 | 0.1 ± 3.0 | 0.2 ± 2.1 | 3.0 | 1.3 |
| Δcontrasta | 133 | 171.2 ± 53.7 | 170.1 ± 55.3 | -1.0 ± 6.4 | -0.9 ± 4.5 | 6.1 | 2.9 |
| Δsessiona | 123 | 160.1 ± 54.0 | 162.8 ± 58.9 | 2.7 ± 12.5 | 1.3 ± 7.4 | 11.0 | 4.7 |
| Δsession_no-outliersa | 111 | 156.4 ± 51.4 | 157.0 ± 53.6 | 0.6 ± 9.5 | 0.3 ± 5.9 | 9.0 | 4.1 |
| Δscannera | 63 | 164.1 ± 56.6 | 162.0 ± 58.3 | -2.1 ± 8.9 | -2.0 ± 7.3 | 8.7 | 4.9 |
| Δalla | 20 | 139.2 ± 43.7 | 131.5 ± 45.9 | -7.7 ± 8.0 | -6.3 ± 6.7 | 7.6 | 5.9 |
| Scanner-agnostic | 171 | 190.8 ± 51.7 | 191.1 ± 49.3 | 0.4 ± 10.1 | 0.9 ± 5.9 | 10.1 | 3.7 |
a Group contains asynchronously calibrated measurements only. vBMD Volumetric bone mineral density, CaHA Calcium hydroxylapatite, RMSE Root mean square error, RMSCV Root mean square coefficient of variation. Δsession_no-outliers comprises the Δsession group following exclusion of outliers, which exceeded the inner boundaries of the 95% confidence interval limit of agreement of the Bland Altman plot in Fig. 4