Substantial amounts of data concerning the-fatigue performance tests are presented. These data contain the information about results that are expressed by means of the fatigue equation parameters Different fatigue tess are included using different types of mixes. The collected information was not similar n all aspects. Some studies included variables. which were not considered by others. The different representations of the fatigue equation makes it necessary to find the relations between the parameters of these different equations in order to study all the data together. The colleeted data were examined statistically to check its consistency; that is to say, they belong to the same population. The Kolmogorov-Smirnov test for goodness of fit was adopted for this purpose.