In comparing the two methods of interest, the Dumas and Sprint methods, the main difference in their results can be
summarized in the RSD, which is a method of measuring variability among sample values. For the Dumas method, it provides very accurate results, with an average RSD near 0.14% compared to 0.98% for the Sprint (data not shown). The direct comparison between the Sprint and Dumas methods has a RSD equal to 1.79%.