The study has been performed with the view to work out a procedure of qualitative and quantitative analysis of results obtained in a diagnostical experiment (the procedure is based on employment of a social-psychological standard; R. Amthauer's intelligence test has been chosen as a diagnostical procedure). Two samples of subjects differing from each other by some important ontogenetic characteristics were estimated by the degree of their closeness to the standard represented in the test. Also qualitative analysis was performed, i. e. establishment of those criterial tasks where the difference between the samples was especially marked. The qualitative and quantitative procedures of processing the test results used in the study can be of significant use in the diagnosis of those peculiarities of mental development which are subject to ontogenetical factors.