Osteoporosis International

, Volume 5, Issue 4, pp 218–227

Quality control of DXA instruments in multicenter trials

  • K. G. Faulkner
  • M. R. McClung
Original Article


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.


Bone densitometry DXA Quality control 


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Copyright information

© European Foundation for Osteoporosis 1995

Authors and Affiliations

  • K. G. Faulkner
    • 1
  • M. R. McClung
    • 1
  1. 1.Oregon Osteoporosis CenterPortlandUSA

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