Table 2. Sensitivity and specificity of osteopenia or osteoporosis by DXA or QCT at the femoral neck, total hip, or L1 – L4 spine in detecting histologically determined low bone volume.
| Diagnosis of osteopenia or osteoporosis by t-scores (BMD t-score ≤ –1) | Compared to low bone volume by biopsy | ||
|---|---|---|---|
| Site and method | Sensitivity | Specificity | Area under ROC curve (95% CI) |
| Femoral neck DXA | 83% | 78% | 0.81 (0.63 – 0.98) |
| Femoral neck QCT | 58% | 78% | 0.68 (0.49 – 0.87) |
| Total hip DXA | 72% | 78% | 0.75 (0.57 – 0.93) |
| Total hip QCT | 64% | 89% | 0.76 (0.60 – 0.92) |
| L1-L4 spine DXA | 47% | 78% | 0.65 (0.46 – 0.85) |
| L1-L4 spine QCT | 53% | 78% | 0.63 (0.46 – 0.85) |
| DXA any site | 89% | 78% | 0.83 (0.67 – 1.00) |
| QCT Any Site | 72% | 78% | 0.75 (0.57 – 0.93) |
DXA = dual-energy X-ray absorptiometry; QCT = quantitative computed tomography; BMD = bone mineral density; ROC = receiving operating characteristic; L1-L4 = lumbar vertebrae 1 through 4.