The methods and approaches for estimating the operating characteristics of the discrete item responses without assuming any mathematical form have been developed and expanded. It has been made possible that, even if the test information function of a given test is not constant for the interval of ability of interest, it is used as the Old Test. The original Old Test consists of 35 test items with three item score categories each. In the present study, the combination of approach (Simple Sum Procedure of the Conditional P.D.F. Approach) and method (Normal Approach Method) were experimented upon. Several subtests of the original Old Test, which contain fifteen or less test items each, were used to find out if each of them can still be used as the Old Test, which maintains the accuracy of estimation reasonably high. (Author/GK)