Lunar DPX-IQ, Operator'S Manual, Page: 150 / 166

I-8 Comparison to Reference Population DPX-IQ Operator’s Manual
I.4 Weight Adjustment
The Age-Matched comparison can be adjusted for body weight by selecting the
appropriate default in the program. Increased weight is associated with higher BMD
values (table I-12). Conversely, decreased weight is associated with lower BMD
values. A weight adjustment is applied for subjects who weigh more or less than the
mean weight. The mean weights are 65 kg for women and 78 kg for men in the US/
Europe database.
Adjustments are applied for weight between 25 and 100 kg.
I.4.1 %Young Adult
The %Young Adult value compares a patient’s BMD with the expected peak bone
mass for a subject of the same sex and nationality. The Young Adult age ranges for
each scan site are as follows:
Table I-12: BMD weight regression for reference females.
Site Regression r See (g/cm 2 )
AP Spine BMD = 0.845 + (0.004 x Weight) 0.14 0.184
Lateral Spine BMD = 0.464 + (0.003 x Weight) 0.21 0.159
Neck BMD = 0.670 + (0.003 x Weight) 0.28 0.134
Ward’s BMD = 0.574 + (0.003 x Weight) 0.21 0.173
Trochanter BMD = 0.460 + (0.003 x Weight) 0.40 0.111
Total Body BMD = 0.886 + (0.004 x Weight) 0.47 0.083
Site
Male
(years)
Female
(years)
Femur 20–45 20–45
AP Spine 20–45 20–45
Forearm 20–50 20–50
Lateral Spine 20–40 20–40
Total Body* 20–55 20–45
* For total body region only.