Resampling methods in Microsoft Excel ® for estimating reference intervals

Computer- intensive resampling/bootstrap methods are feasible when calculating reference intervals from non-Gaussian or small reference sam-ples. Microsoft Excel ® in version 2010 or later includes natural functions, which lend themselves well to this purpose including recommended inter-polation procedures for estimating 2.5 and 97.5 percentiles. The purpose of this paper is to introduce the reader to resampling estimation techniques in general and in using Microsoft Excel ® 2010 for the purpo-se of estimating reference intervals in particular. Parametric methods are preferable to resampling methods when the distributions of observations in the reference samples is Gaussian or can tran-sformed to that distribution even when the number of reference samples is less than 120. Resampling methods are appropriate when the distribu-tion of data from the reference samples is non-Gaussian and in case the number of reference individuals and corresponding samples are in the order of 40. At least 500-1000 random samples with replacement should be taken from the results of measurement of the reference samples