The use of the range in place of the standard deviation as a measure of dispersion has long been recognized as a convenient and easily calculated statistic. Possibly its most notable employment has been in the industrial statistician's quality control charts. A statistic based upon the range is described below which may be used to test whether one of a group of means may be considered to be a straggler from all or some of the others in a two-way analysis of variance.
"Testing a Straggler Mean in a Two-Way Classification Using the Range." Ann. Math. Statist. 23 (1) 126 - 132, March, 1952. https://doi.org/10.1214/aoms/1177729490