Quantitative cytology of oral smears. A comparison of two methods of measurement.

Previous quantitative cytologic studies employing planimetry to assess oral smears established a "discriminant line" for separating normal and abnormal cases. The use of the Vids V semiautomatic image analysis system to make these measurements was analyzed to determine whether the results obtained by the two methods were comparable. In measuring the same cells by both methods, no significant variation in nuclear size was detected; however, there was a statistically significant variation in the measurements of cytoplasmic area. Further analysis suggested that the cytoplasmic areas differed by a constant amount, not a constant proportion, between the two methods; this may be due to the ability of the Vids V system to more clearly display the cell boundaries. The appropriateness of techniques for comparing different methods is discussed.