Kellogg Canada, Inc., Mississauga, Ontario L4W 5S1, Canada.
Nutr Rev. 2013 Jun;71(6):332-42. doi: 10.1111/nure.12025. Epub 2013 May 2.
Dual X-ray absorptiometry (DXA) has a range of clinical applications, from assessing associations between adipose or lean body mass and the risk of disease to measuring the effects of dietary interventions on adipose deposition and oxidation and/or muscle accumulation. Many lifestyle-related studies, however, are short- to medium-term interventions, and inter- or intradevice variation between DXA scanners can facilitate type I and type II errors during data analysis. Studies demonstrate that variation in body composition measurements exist not only between DXA instruments using fan-beam and pencil-beam technologies but also between DXA instruments produced by different manufacturers. Moreover, studies show inter- and intrainstrument variation between identical DXA instruments. Such inter- and intrascan variability between instruments can be compounded by the particular patient population being investigated. The objective of this review is to discuss inter- and intradevice variation of DXA instruments and to outline quality control procedures that should be implemented prior to initiating short-term single or multicenter clinical trials that use DXA to investigate the effects of an intervention on loss or accretion of lean or fat mass.
双能 X 线吸收法（DXA）在临床中有广泛的应用，从评估脂肪或瘦体重与疾病风险之间的关系，到测量饮食干预对脂肪沉积和氧化和/或肌肉积累的影响。然而，许多与生活方式相关的研究都是短期到中期的干预，DXA 扫描仪之间的仪器内或仪器间差异可能会在数据分析过程中导致 I 型和 II 型错误。研究表明，不仅使用扇形束和铅笔束技术的 DXA 仪器之间，而且不同制造商生产的 DXA 仪器之间的体成分测量值也存在差异。此外，研究表明，相同 DXA 仪器之间存在仪器内和仪器间差异。仪器之间的这种仪器内和仪器间变异性可能会因所研究的特定患者人群而加剧。本综述的目的是讨论 DXA 仪器的仪器内和仪器间差异，并概述在启动使用 DXA 来研究干预对瘦体重或脂肪体重损失或增加的短期单中心或多中心临床试验之前，应实施的质量控制程序。
