A BASIC program for computer-assisted point-counting techniques.

Description is given of a BASIC program running on inexpensive microcomputers (Commodore CBM 64, SX 64 and Apple II[e]) to facilitate and accelerate substantially the point-counting technique, one of the most widely used methods in the determination of such stereologic parameters as VV, AA, SV, BA, JV, KV and NV. The program aims to alleviate the most laborious manipulations required to obtain estimates of stereologic parameters and their statistical assessments. The program requires the declaration of the coherent grid constants, the desired stereologic parameters and the definition of up to ten keys of the computer keyboard to be used as score counters for the registration of particular grid-object events. After the registration of these decision events, the program is used to count points, intersections, transsections, number of profiles and tangents of a coherent test grid system with the objects of interest in a histologic section. The computer then calculates the stereologic parameters as well as the standard deviation and standard error of mean of these parameters, using the contents of the score counters as arguments. The flexibility of the program allows for the construction of investigator-defined parameters that can be expressed as a ratio of particular events as well as the use of standard stereologic parameters. While the program has been successfully utilized by nonprogrammers following basic instruction, knowledge of the elementary principles of stereology is a must in utilizing all of the possibilities of the program.