Abstract

Clinicians have a need to grade the magnitude or the severity of the functions and qualities they assess in their examinations. They do this to record the stage of the disease or condition of interest. The grade provides a reference to which any future grading may be compared and the grade may also be used in deciding deviations from normality. The clinicians questions are "is there or is there not a deviation from normality?" or "has there or has there not been a change in this condition?" The decision is whether the 'observed' finding differs from the 'expected' value. The expected value may be either a grade recorded previously or the 'normal' value. For all systems used for grading a continuous variable, there is a statistical probability that there will be a difference in the assigned grades when there is actually no difference in the two conditions being compared. Similarly, there will be times when the assigned grades remain the same even though the condition has changed.

© 1990 Optical Society of America