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Comparisons between groups: mean differences only (A), mean differences driven particularly by differences at the upper quantiles (B), no mean difference yet different distributions (C). Note that variance is also higher in (B) and (C) than in (A). Figure adapted from Beyerlein A. Quantile regression—opportunities and challenges from a user's perspective. Am J Epidemiol 2014; 180(3): 330–31, by permission of Oxford University Press.
