本研究以磁振造影法(MRI法)檢驗三種生物電阻儀(BIA儀)之準確性，並探討參種BIA儀之間的相關性。以此建立身體組成與體脂肪測量的標準，提供最為準確的健康訊息。本研究採用準確性最高MRI法來評估體脂肪百分比，以相同受試者進行身體組成測量，評估手握式、直立式、全身式三種不同測量型態的BIA儀的準確性。實驗結果顯示手握式及站立式BIA儀與MRI法未達顯著差異，而全身式BIA儀與MRI達顯著差異，三種BIA儀與MRI的相關條、數分別為r=0.48、0.62和0.6(p<.05)，此結果顯示全身式BIA儀的準確性並非完全可信，與實際值間仍有差距存在。隨著世界文明的演進，人類生活中減少了身體勞動，導致身體組成的健康議題受到重視，目前市面上常見BIA測量儀為相當方便精巧的檢驗器材，然而在繁多眾多儀器的商業競爭下，讓民眾能擁有準確可信的體脂肪百分比數據，以得到正確健康訊息，確實為一不容忽視的課題。

As civilization has evolved, human beings have reduced the amount of physical labor that is done in daily life. This has caused serious health problems, and now people pay more attention to physique and fitness issues. There are many methods to assess body composition, and this equipment is simple to operate. Therefore, accuracy of the equipment has become an important issue. Thus becomes a doubtable point, it is necessary to standardize an exact assessment in measuring the percentage of body fat. The current methodologies that people often use are Body Mass Index (BMI), Bioelectrical Impedance Analysis (BIA), skin fold measurement and magnetic resonance imaging (MRI). Among these methods, BIA is considered to be convenient and has become more and more popular. However, because of doubts concerning the accuracy of many measuring devices, a precise assessment of BIA needs to be conducted. The purpose of this study was to assess the percentage of body fat by MRI, and to compare it to BIA. We carried out three BIA assessments on subjects. After the experiment, we took the MRI measurement as a criterion, correcting the result of other methods and comparing the variation of four assessments. MRI can truly provide the most trustworthy assessment.