ESR SED RATE IS A BLOOD TEST MEASURES HOW QUICKLY RED BLOOD CELLS (ERYTHROCYTES) SETTLE IN A TEST TUBE IN ONE HOUR. THE MORE RED CELLS THAT FALL TO THE BOTTOM OF THE TEST TUBES IN ONE HOUR, THE HIGHER THE SED RATE. SED RATE IS DONE TO FIND OUT IF INFLAMMATION IS PRESENT, CHECK ON THE PROGRESS OF A DISEASE, AND TO SEE HOW WELL TREATMENT IS WORKING. SED RATE TEST ISN’T A STAND-ALONE DIAGNOSTIC TOOL, BUT IT MAY HELP YOUR DOCTOR DIAGNOSE OR MONITOR THE PROGRESS OF AN INFLAMMATORY DISEASE.