Quality control of DXA instruments in multicenter trials

Osteoporos Int. 1995;5(4):218-27. doi: 10.1007/BF01774010.


Dual-energy X-ray absorptiometry (DXA) has become the measurement of choice for multicenter trials with bone density endpoints. When performing DXA measurements with several different systems, it is important to implement a quality assurance program to guarantee that any observed density changes are real and not due to machine and/or operator variability. In this study, we present a series of procedures based on phantom measurements designed to monitor DXA instrument stability. Techniques for longitudinal evaluation of machine performance and cross-calibration of instruments are described. These procedures are then demonstrated using quality assurance data collected from a number of different DXA scanners. Together these methods provide a defined approach to instrument quality control. Though based primarily on the use of spinal phantoms, these procedures can be generalized for use in any multicenter DXA study.

MeSH terms

  • Absorptiometry, Photon / instrumentation*
  • Absorptiometry, Photon / standards
  • Bone Density / physiology*
  • Calibration
  • Clinical Trials as Topic
  • Humans
  • Longitudinal Studies
  • Multicenter Studies as Topic
  • Quality Control