The number of bacteria, yeast, crystals and mucous must be estimated.

1. Examine 10 fields under high power (40X) magnification. Use phase-contrast if needed.
2. Determine the average of each element found and record the findings according to the following criteria:
   • Element fills <1/4 of each field = trace
   • Element fills about 1/4 of each field = 1+
   • Element fills about 1/2 of each field = 2+
   • Element fills about 3/4 of each field = 3+
   • Element fills total field = 4+