A good check to see if your Complete Blood Counts on your patient results are valid is the
“RULE OF THREE”
Rule #1 Hgb X 3 = Hct +/-2
Rule #2 RBC x 3.3 = Hgb +/- 1.5
Rule #3 RBC x 9 = Hct +/3
Note : The laboratory must verify
calibration on the instrument
every 6 months or on an “as
needed” basis to ensure
accuracy of the system.
Source Hematology