Bioimpedance analysis (BIA) is accepted for the assessment of total-body water (TBW), intracellular fluid (ICF) and extracellular fluid (ECF). We aimed to compare precision and accuracy of single and multi-frequency-BIA to direct estimation methods (DEMs) of TBW, ECF, and ICF in hemodialysis patients. Linear regression analysis of volume estimates in 49 patients by single- and multi-frequency-BIA correlated significantly with DEMs. Bland-Altman analysis (BAA) found systemic bias for ECF single-frequency-BIA vs. ECF-DEMs. No other systematic biases were found. Proportional errors were found by BAA of ICF and ECF assessments with single- and multi-frequency bioimpedance spectroscopy compared to the DEMs. Comparisons of indirect methods (IEMs) to DEMs showed no significant differences and proportional errors. Root mean-squared-error analysis suggested slightly better accuracy and precision of ICF single-frequency-BIA vs. DEMs over ICF multi-frequency-BIA and IEMs to DEMs, and slightly better performance for ECF multi-frequency-BIA over both respective other methods. Compared to DEMs, there is slightly better accuracy for ECF multi- over single-frequency-BIA and ICF single- over multi-frequency-BIA. However the margin of differences between direct and indirect methods suggests that none of the analyzed methods served as a true "gold standard", because indirect methods are almost equally precise compared to DEMs.

中文翻译：

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通过生物阻抗，直接同位素和稀释方法比较慢性血液透析患者的体液量估计值。

生物阻抗分析（BIA）用于评估全身水（TBW），细胞内液（ICF）和细胞外液（ECF）。我们旨在将单频和多频BIA的准确性和准确性与血液透析患者的TBW，ECF和ICF的直接估计方法（DEM）进行比较。通过单频和多频BIA对49位患者的血容量估计值进行线性回归分析与DEM显着相关。Bland-Altman分析（BAA）发现ECF单频BIA与ECF-DEM的系统性偏差。没有发现其他系统偏见。与DEM相比，通过单频和多频生物阻抗谱对ICF和ECF进行的BAA评估发现了比例误差。间接方法（IEM）与DEM的比较显示没有显着差异和比例误差。均方根误差分析表明，ICF单频BIA相对于DEF而言，ICF单频BIA的精度和精度稍高一些，而IEM相对于DEM而言，则优于EEM；而ECF多频BIA的性能则略好于彼此方法。与DEM相比，ECF单频多频BIA和ICF单频多频BIA的精度更高。但是，直接方法和间接方法之间的差异表明，没有一种分析方法可作为真正的“黄金标准”，因为与DEM相比，间接方法几乎同样精确。与DEM相比，ECF单频BIA和ICF单频BIA的精度更高。但是，直接方法和间接方法之间的差异表明，没有一种分析方法可作为真正的“黄金标准”，因为与DEM相比，间接方法几乎同样精确。与DEM相比，ECF单频多频BIA和ICF单频多频BIA的精度更高。但是，直接方法和间接方法之间的差异表明，没有一种分析方法可作为真正的“黄金标准”，因为与DEM相比，间接方法几乎同样精确。