OsteoEd

Common Questions

What is the most accurate/precise method of measuring bone density? What are other central bone mass measurement methods?

DXA has emerged as the best technique for testing bone density because of its speed, low radiation exposure, relatively low cost, and reasonable accuracy and reproducibility.

Comparison of Available Technologies
Method Body site Advantages Disadvantages Precision Error Accuracy Error
DXA (dual x-ray absorptiometry)
  • Hip
  • Spine
  • Total body
  • Multiple sites assessed
  • Low radiation (1 to 5 millirems) Short scan time
  • Portable peripheral-site scanning units
  • Accuracy errors in vivo
  • High cost
  • Influenced by extra-osseous calcium
  • Non-portable
 1 to 2% 3 to 9%
DPA (dual photon absorptiometry)
  • Hip
  • Spine
  • Total body
  • Multiple sites assessed
  • Low radiation (1 to 5 millirems)
  • Long scan time
  • Expensive
  • Medicare doesn't reimburse
 2 to 5% 3 to 10%
QCT (Quantitative computed tomography)
  • Hip
  • Spine
  • Total body
  • Discriminates trabecular from cortical bone
  • High resolution
  • High radiation dose (50 millirems)
  • High cost
 2 to 4% 5 to 15%
Adapted from:
  1. Osteoporosis: Cost-effectiveness analysis and review of the evidence for prevention, diagnosis, and treatment. Osteoporosis International 1998; 8(S4): S7-S86.
  2. World Health Organization: Assessment of fracture risk and its application to screening for postmenopausal osteoporosis. Report of a WHO Study Group. Geneva Switzerland: World Health Organization 1994; (Technical.
Last updated 2009-05-26