Combest Travis M, Khan Joetta, Tufano James J, Lane Michael, Watson Nora L, Altom Kelley R, Moon Jordan R
Department of Nutrition Services, Walter Reed National Military Medical Center, Bethesda, MD 20889, USA.
Division of Health Science and Human Performance, Concordia University of Chicago, River Forest, IL 60305, USA.
Mil Med. 2025 Feb 27;190(3-4):e642-e648. doi: 10.1093/milmed/usae439.
A comparison of body composition assessments using military circumferences to bioelectrical impedance analysis (BIA) and the reference standard dual-energy X-ray absorptiometry (DEXA) can gauge effectiveness of assessments. High-frequency (500 KHz) direct segmental multifrequency bioelectrical impedance analysis (DSM-BIA) accurately calculates total water mass and body fat% (BF%), but it is unknown whether higher frequencies (1,000 KHz) increase measurement accuracy. The purpose was to compare DSM-BIA 500, DSM-BIA 1000, the DoD Circumference Method (CM), and the reference-standard DEXA.
Design: Cross sectional, observational study. Participants/Setting: A total of 62 participants from the military healthcare system (n = 25 males, 38.8 ± 11.4 years, n = 37 females 43.7 ± 15.95 years) were measured in an outpatient clinic setting. Statistical Analysis: BF% was estimated via DEXA, DSM-BIA 500, DSM-BIA 1000, and CM to identify the relationship between methods using Pearson correlation, intraclass correlation coefficients (ICCs), and Bland-Altman plots. The study was approved by the IRB from Walter Reed National Military Medical Center at Bethesda and Concordia University Chicago.
Circumference Method BF% was moderately correlated with DSM-BIA 500 (males r = 0.63, ICC = 0.76; females r = 0.77, ICC = 0.85), DSM-BIA 1000 (males r = 0.59, ICC = 0.74; females r = 0.77, ICC = 0.85), and DEXA (males r = 0.62, ICC = 0.62; females r = 0.73, ICC = 0.82). DSM-BIA 500 BF% was strongly correlated with DSM-BIA 1000 (males r = 0.99, ICC = 0.99; females r = 0.99, ICC = 0.99) and DEXA (males r = 0.93, ICC = 0.94; females r = 0.89, ICC = 0.89). Lastly, DSM-BIA 1000 BF% was also strongly correlated with DEXA (males r = 0.93, ICC = 0.94; females r = 0.84, ICC = 0.90) (P for each reported r < 0.01). Bland-Altman analysis confirmed an overall mean bias of -1.72% CM vs. DEXA in females, indicating the tendency of CM to underestimate BF% compared to DEXA limits of agreement from -14.24 to 10.8. There was an upward slope of the linear relationship between the bias and mean of the measures (Beta = 0.34, P = 0.01). In the full cohort, there was an overall mean bias of 1.14% of CM vs. DSM BIA 1000, with CM tending to overestimate BF% compared to DSM BIA 1000 with limits of agreement -11.13 to 13.41%. There is an upward slope line of the linear relationship between the bias and the mean of the measures (Beta = 0.17, P = .03).
This study found that CM BF% was moderately correlated with DSM-BIA 500 kHz, DSM-BIA 1,000 kHz BIA, and DEXA. Both DSM-BIA 500 and DSM-BIA 1,000 kHz strongly correlated well with DEXA implying that there was no further increase in correlation with increased frequency. Additionally, there was proportional bias in BF% in the female group between CM and DEXA and in the total group between CM and DSM BIA 1000.
使用军事测量围度与生物电阻抗分析（BIA）以及参考标准双能X线吸收法（DEXA）对身体成分评估进行比较，可以衡量评估的有效性。高频（500 KHz）直接节段多频生物电阻抗分析（DSM - BIA）能够准确计算总体水质量和体脂百分比（BF%），但尚不清楚更高频率（1000 KHz）是否会提高测量准确性。本研究旨在比较DSM - BIA 500、DSM - BIA 1000、国防部围度法（CM）以及参考标准DEXA。
设计：横断面观察性研究。参与者/研究地点：共有62名来自军事医疗系统的参与者（n = 25名男性，年龄38.8 ± 11.4岁；n = 37名女性，年龄43.7 ± 15.95岁）在门诊环境中接受测量。统计分析：通过DEXA、DSM - BIA 500、DSM - BIA 1000和CM估计BF%，使用Pearson相关性、组内相关系数（ICC）以及Bland - Altman图来确定各方法之间的关系。该研究获得了贝塞斯达沃尔特·里德国家军事医疗中心和芝加哥康考迪亚大学的机构审查委员会（IRB）批准。
围度法BF%与DSM - BIA 500（男性r = 0.63，ICC = 0.76；女性r = 0.77，ICC = 0.85）、DSM - BIA 1000（男性r = 0.59，ICC = 0.74；女性r = 0.77，ICC = 0.85）以及DEXA（男性r = 0.62，ICC = 0.62；女性r = 0.73，ICC = 0.82）呈中度相关。DSM - BIA 500的BF%与DSM - BIA 1000（男性r = 0.99，ICC = 0.99；女性r = 0.99，ICC = 0.99）以及DEXA（男性r = 0.93，ICC = 0.94；女性r = 0.89，ICC = 0.89）呈强相关。最后，DSM - BIA 1000的BF%与DEXA也呈强相关（男性r = 0.93，ICC = 0.94；女性r = 0.84，ICC = 0.90）（各报告的r值对应的P < 0.01）。Bland - Altman分析证实，女性中CM与DEXA相比总体平均偏差为 - 1.72%，表明与DEXA相比，CM有低估BF%的趋势，一致性界限为 - 14.24至10.8。偏差与测量均值之间的线性关系存在向上的斜率（β = 0.34，P = 0.01）。在整个队列中，CM与DSM BIA 1000相比总体平均偏差为1.14%，与DSM BIA 1000相比，CM有高估BF%的趋势，一致性界限为 - 11.13至13.41%。偏差与测量均值之间的线性关系存在向上的斜率线（β = 0.17，P = 0.03）。
本研究发现CM的BF%与DSM - BIA 500 kHz、DSM - BIA 1000 kHz BIA以及DEXA呈中度相关。DSM - BIA 500和DSM - BIA 1000 kHz与DEXA均呈强相关，这意味着随着频率增加相关性并未进一步提高。此外，女性组中CM与DEXA之间以及整个组中CM与DSM BIA 1000之间在BF%方面存在比例偏差。
