Cross-calibration of Prodigy and Horizon A densitometers and precision of the Horizon A densitometer

Abstract Introduction/background We performed this study to enable a reliable transition for clinical study participants and patients from a GE Lunar Prodigy to a Hologic Horizon A dual-energy X-ray absorptiometry (DXA) scanner and to assess the reproducibility of measurements made on the new DXA scanner. Methodology Forty-five older adults had one spine, hip and total body scan on a Prodigy dual-energy X-ray absorptiometry (DXA) scanner and two spine, hip, and total body scans, with repositioning, on a new Hologic Horizon A DXA scanner. Linear regression models were used to derive cross calibration equations for each measure on the two scanners. Precision (group root-mean-square average coefficient of variation) of bone mineral density (BMD) of the total hip, femoral neck, and lumbar spine (L1-L4), and total body fat, bone, and lean mass, appendicular lean mass, and trabecular bone score (TBS) was assessed using the International Society of Clinical Densitometry's (ISCD's) Advanced Precision Calculation Tool. Results Correlation coefficients for the BMD and body composition measures on the two scanners ranged from 0.94 to 0.99 (p Conclusions The differences in BMD and body composition values on the two scanners illustrate the importance of cross-calibration to account for these differences when transitioning clinical study participants and patients from one scanner to another.