School of Health, University of the Sunshine Coast, Sippy Downs, Australia; School of Human Movement and Nutrition Sciences, The University of Queensland, Brisbane, Australia; Sunshine Coast Health Institute, Birtinya, Australia.
School of Human Movement and Nutrition Sciences, The University of Queensland, Brisbane, Australia.
J Clin Densitom. 2024 Oct-Dec;27(4):101522. doi: 10.1016/j.jocd.2024.101522. Epub 2024 Aug 24.
Reliable peripheral quantitative computed tomography (pQCT) assessment is essential to the accurate longitudinal reporting of bone and muscle quality. However, the between-day reliability of pQCT and the influence of age on outcome reliability is currently unknown.
To quantify the same- and between-day reliability of morphological pQCT at proximal and distal segments of the forearm, shank, and thigh, and explore the influence of participant body size, age, and sex on outcome reliability.
Men and women (49 % female, 18-85 years, n=72-86) completed two consecutive-day pQCT testing sessions, where repeat measurements were conducted on day-one for technical error, and between-day for biological error quantification. Testing was undertaken following best practice body composition testing guidance, including standardized presentation and consistent time-of-day.
All measurements of bone were classified as having 'good' to 'excellent' reliability [intraclass correlation coefficient (r=0.786- 0.999], as were measurements of muscle area (ICC r=0.991-0.999) and total fat (r=0.996-0.999). However, between- and same-day muscle density measurements at the thigh and forearm were classified as 'poor' (r=0.476) and 'moderate' (r=0.622), respectively. Likewise, intramuscular fat area at the thigh was classified as 'moderate' (r=0.737) for between-day measurement. Biological error was inflated compared to technical error by an average of 0.4 % for most measurements. Error values tended to increase proportionally with the amount of tissue quantified and males had significantly greater biological error for measurement of distal tibial bone (p<0.002) and trabecular area (p<0.002). Biological error was inflated among older adults for measurement of forearm muscle density (p<0.002).
Most pQCT outcomes can be implemented with confidence, especially outcomes that assess bone area and density at any of the radial, tibial, and femoral sites investigated herein. However, it is important to account for the influence of biological measurement error in further studies, especially for muscle and intramuscular fat outcomes derived by pQCT.
可靠的外周定量计算机断层扫描（pQCT）评估对于准确的骨和肌肉质量纵向报告至关重要。然而，目前尚不清楚 pQCT 的日内和日间可靠性，以及年龄对结果可靠性的影响。
定量评估前臂、小腿和大腿近端和远端节段形态 pQCT 的同日和日间可靠性，并探讨参与者的体型、年龄和性别对结果可靠性的影响。
男性和女性（49%为女性，年龄 18-85 岁，n=72-86）完成了两次连续两天的 pQCT 测试，在第一天进行重复测量以进行技术误差量化，在第二天进行日间测量以进行生物误差量化。测试按照最佳的身体成分测试指南进行，包括标准化呈现和一致的时间。
所有骨测量均被归类为具有“良好”至“优秀”的可靠性[组内相关系数（ICC r=0.786-0.999]，肌肉面积（ICC r=0.991-0.999）和总脂肪（r=0.996-0.999）的测量也是如此。然而，大腿和前臂的日间和同日肌肉密度测量被归类为“差”（r=0.476）和“中等”（r=0.622）。同样，大腿的肌内脂肪面积的日间测量被归类为“中等”（r=0.737）。与技术误差相比，大多数测量的生物误差平均增加了 0.4%。误差值倾向于与被量化的组织量成比例增加，男性在测量胫骨远端骨（p<0.002）和小梁面积（p<0.002）时的生物误差显著更大。对于前臂肌肉密度的测量，老年成年人的生物误差增加（p<0.002）。
大多数 pQCT 结果可以有信心地实施，特别是评估此处研究的桡骨、胫骨和股骨部位的骨面积和密度的结果。然而，在进一步的研究中，重要的是要考虑生物测量误差的影响，特别是对于 pQCT 得出的肌肉和肌内脂肪结果。
