Abstract：
This study aims to examine the validity and reliability of the UltraScan650™, a portable ultrasound device, used to measure BMD at the 1/3rd radius position. Fifty-two female first responders and healthcare providers were assessed using DXA (forearm, femur, lumbar, and total body) and the UltraScan650™. Fat and lean mass were also assessed using the DXA. Pearson correlations, Bland-Altman plots, t-tests, and linear regressions were used to assess validity. Intra-class correlation (ICC) coefficients were used to assess reliability. Inter-rater reliability and repeatability were good (ICC = 0.896 [0.818; 0.942], p < 0.001) and excellent (ICC = 0.917 [0.785; 0.989], p < 0.001), respectively. BMD as measured by the UltraScan650™ was weakly correlated to the DXA (r = 0.382 [0.121; 0.593], p = 0.0052). Bland-Altman plots revealed that the UltraScan650™ underestimated BMD (-0.0569 g/cm2), this was confirmed with a significant paired t-test (p < 0.001). A linear regression was performed (0.4744 × UltraScan650™ + 0.4170) to provide more information as to the issue of agreement. Bland-Altman plots revealed a negligible bias, supported by a paired t-test (p = 0.9978). Pearson\'s correlation revealed a significant relationship (r = -0.771 [-0.862; -0.631], p < 0.0001) between adjusted UltraScan650™-DXA and the average of the two scans (i.e., adjusted UltraScan650™ and DXA), suggesting a proportional constant error and proportional constant variability in measurements of BMD from the UltraScan650™. The UltraScan650™ is not a valid alternative to DXA for diagnostic purposes; however, the UltraScan650™ could be used as a screening tool in the clinical and research setting given the linear transformation is employed.
摘要：
本研究旨在检验UltraScan650™的有效性和可靠性，便携式超声波设备，用于测量1/3半径位置的BMD。使用DXA（前臂，股骨,腰椎,和整体）和UltraScan650™。还使用DXA评估脂肪和瘦体重。皮尔逊相关性，Bland-Altman阴谋,t检验,和线性回归用于评估有效性。使用类内相关系数(ICC)来评估可靠性。评分者间的可靠性和重复性良好(ICC=0.896[0.818;0.942]，p<0.001）和优秀（ICC=0.917[0.785；0.989]，p<0.001)，分别。UltraScan650™测得的BMD与DXA弱相关(r=0.382[0.121;0.593],p=0.0052)。Bland-Altman地块显示UltraScan650™低估了BMD（-0.0569g/cm2），这通过显著的配对t检验(p<0.001)得到证实.进行线性回归(0.4744×UltraScan650™+0.4170)以提供关于协议问题的更多信息。布兰德-奥特曼的阴谋显示出微不足道的偏见，由配对t检验支持(p=0.9978)。皮尔逊相关性揭示了一种显著的关系(r=-0.771[-0.862；-0.631]，调整后的UltraScan650™-DXA与两次扫描的平均值之间的p<0.0001）（即，调整后的UltraScan650™和DXA），这表明UltraScan650™在测量BMD时存在比例恒定误差和比例恒定可变性。UltraScan650™不是用于诊断目的的DXA的有效替代品;但是,如果采用线性变换，UltraScan650™可用作临床和研究环境中的筛选工具。
