A method and apparatus are disclosed for measuring characteristics of cells, such as red blood cells, and for analyzing parameters of the cell characteristics to define a patient's blood. These parameters may be compared for resemblance to predetermined reference characteristic values for a blood cell pathological condition such as a specific kind of anemia or for a normal blood. A report may be generated showing such resemblance to an anemia or to a normal blood. A report may be generated showing parameters of a multivariate dispersion of distribution for a subpopulation of biconcave cells, an indication of skewness of the distribution of the cells with regard to shape variations in central pallor size; the proportion of abnormal kinds of cells found, and closeness of blood to several specific anemias. To expedite the system, a plurality of microprocessors are employed with one microprocessor controlling the imaging means and the summing of measured characteristics while one or more additional microprocessors are measureing characteristics and analyzing the digitized image signals. An improved method of measuring central pallor size is provided.