PCS-I--a point counting stereology program for cell biology.

PCS-I is a versatile BASIC program designed to collect and process stereological point counting data from electron micrographs of cells. The program can accept the point counts from three sources: (i) a set of user-definable keys programmed as counters; (ii) a numeric pad that enters counts line by line; and (iii) a data tape cartridge. The program calls for all the information needed to solve stereological equations and then helps the user to interpret the suitability of the sample size by drawing error curves. The coefficients of the stereological equations and the output headings can be readily modified to accommodate a new set of experimental parameters, which gives a substantial amount of flexibility to the program. PCS-I is easy to use and offers a practical solution to the problem of data management for biological stereology.