There are two methods of ESR, we are mentioned below. Westergren method: The Westergren method calculates the length (in millimetres) at which anticoagulated whole blood red blood cells settle to the bottom of a standardised, upright, elongated tube over the course of an hour as a result of gravity. The Westergren tube is the one used for the test. Wintrobe method: Red blood cell loss is assessed in millimetres after one hour in a tube filled with EDTA-anticoagulated blood that hasn't been given any additional diluent. This method is less accurate than the Westergren method due to the shorter column and smaller maximum probable anomalous value.