[Use of nonparametric methods in medicine. VI. Evaluation using dependence by rank]

The authors deal with the evaluation of dependence between two quantitative variables. They analyze Spearman's and Kendall's rank correlation coefficients. The procedure is explained on examples. Decision taking between the zero and alternative hypothesis is made possible by the enclosed tables of critical values. When the number of data is higher than 30, the significance of the two coefficients can be evaluated by means of the testing characteristic with a normal distribution.