J Bone Metab.  2015 May;22(2):45-49. 10.11005/jbm.2015.22.2.45.

Result of Proficiency Test and Comparison of Accuracy Using a European Spine Phantom among the Three Bone Densitometries

• Park AJ
• Choi JH
• Kang H
• Park KJ
• Kim HY
• Kim SH
• Kim DY
• Park SH
• Ha YC

• KMID: 2170087
• DOI: http://doi.org/10.11005/jbm.2015.22.2.45

Abstract

BACKGROUND
Although dual energy X-ray absorptiometry (DXA) is known to standard equipment for bone mineral density (BMD) measurements. Different results of BMD measurement using a number of different types of devices are difficult to use clinical practice. The purpose of this study was to evaluate discrepancy and standardizations of DXA devices from three manufactures using a European Spine Phantom (ESP).
METHODS
We calculated the accuracy and precision of 36 DXA devices from three manufacturers (10 Hologic, 16 Lunar, and 10 Osteosys) using a ESP (semi-anthropomorphic). The ESP was measured 5 times on each equipment without repositioning. Accuracy was assessed by comparing BMD (g/cm2) values measured on each device with the actual value of the phantom. Precision was assessed by the coefficient of variation (CVsd).
RESULTS
Lunar devices were, on average, 22%, 8.3%, and 5% overestimation for low (L1) BMD values, medium (L2), and high (L3) BMD values. Hologic devices were, on average, 6% overestimation for L1 BMD, and 5% and 6.2% underestimation for L2 and L3 BMD values. Osteosys devices was, on average, 12.7% (0.063 g/cm2), 6.3% (0.062 g/cm2), and 5% (0.075 g/cm2) underestimation for L1, L2, and L3, respectively. The mean CVsd for L1-L3 BMD were 0.01%, 0.78%, and 2.46% for Lunar, Hologic, and Osteosys devices respectively.
CONCLUSIONS
The BMD comparison in this study demonstrates that BMD result of three different devices are significant different between three devices. Differences of BMD between three devices are necessary to BMD standardization.

Keyword

Bone density; Densitometry; Lumbar vertebrae; Reference standards

MeSH Terms

Absorptiometry, Photon
Bone Density
Densitometry*
Lumbar Vertebrae
Spine*

Figure

• 

  Fig. 1 Individual bone mineral density (BMD) values of and Lunar (n=16 devices, 80 measurements), Hologic (n=10 devices, 50 measurements), and Osteosys (n=10 devices, 50 measurements) devices.

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