Table 3.
Diaphyseal DXA Versus pQCT Indices: Correlation Coefficients and Mean Differences
| DXA | pQCT | Spearman’s ρ | DXA-pQCT mean difference (−2 to +2 SD) |
|---|---|---|---|
| Bone mineral apparent density (BMAD, g/cm3) | Total volumetric BMD (tvBMD, g/cm3) | +0.74 | −0.281 (−0.401 to −0.161) |
| Periosteal CSA (pCSA, mm2) | Periosteal CSA (pCSA, mm2) | +0.96 | 31.27 (2.72 to 59.82) |
| Section modulus (Z, mm3) | Polar strength-strain index (SSI, mm3) | +0.96 | −18.62 (−62.47 to 25.24) |
| Z fall-strength Ratio | SSI fall-strength ratio | +0.88 | −0.01 (−0.05 to 0.02) |
| Cortical CSA (cCSA, mm2) | Cortical/subcortical CSA (cscCSA, mm2) | +0.98 | 2.86 (−4.25 to 9.96) |
| Cortical CSA (cCSA, mm2) | Cortical CSA (cCSA, mm2) | +0.98 | 4.51 (−2.32 to 11.35) |
| Intramedullary CSA (imCSA, mm2) | Intramedullary CSA (imCSA, mm2) | +0.84 | 28.41 (1.41 to 55.41) |
| Cortical thickness (CWT, mm) | Cortical thickness (CWT, mm) | +0.90 | −0.51 (−1.00 to −0.03) |