448 | wileyonlinelibrary.com/journal/ijlh Int J Lab Hem. 2017;39:448–457. © 2017 John Wiley & Sons Ltd Received: 20 November 2016 | Accepted: 3 April 2017 DOI: 10.1111/ijlh.12693 ORIGINAL ARTICLE ICSH recommendations for modified and alternate methods measuring the erythrocyte sedimentation rate A. Kratz 1 | M. Plebani 2 | M. Peng 3 | Y.K. Lee 4 | R. McCafferty 5 | S.J. Machin 6 | on behalf of the International Council for Standardization in Haematology (ICSH) 1 Columbia University Medical Center and New York Presbyterian Hospital, New York, NY, USA 2 Department of Laboratory Medicine, University Hospital of Padua, Padua, Italy 3 National Center for Clinical Laboratories (NCCL), Beijing, China 4 Department of Laboratory Medicine, Hallym University College of Medicine & Hallym University Sacred Heart Hospital, Anyang, Korea 5 St. James Hospital, Dublin, Ireland 6 University College London Hospitals, London, UK Correspondence Alexander Kratz, NewYork-Presbyterian Hospital, Automated Core Laboratory, New York, NY 10032. Email: ak2651@cumc.columbia.edu Funding information This study was financially supported by the ICSH. The ICSH is a not-for-profit organization sponsored by unrestricted educational grants from its corporate and affiliate members who are listed in the attached in Data S1. Abstract Introduction: The gold standard for the determination of the erythrocyte sedimenta- tion rate (ESR) is the Westergren method. Other methods to measure the ESR have become available. They range from modest modifications of the Westergren method to very different methodologies. The ICSH therefore established a Working Group to investigate these new approaches and compile recommendations for their validation and verification. Methods: A panel of six experts in laboratory hematology examined the peer-reviewed literature and EQA surveys from over 6000 laboratories on four continents perform- ing ESR testing. This information was used to create lists of ESR instrument manufac- turers and their methods. Results: Only 28% of laboratories surveyed used the unmodified Westergren method, while 72% of sites used modified or alternate methods. Results obtained with the new instruments could differ from results obtained with the Westergren method by up to 142%. Different non-Westergren methods showed differences from each other of up to 42%. The new methods were often significantly faster, safer, and less labor- intensive. They reduced costs and often used standard EDTA tubes, eliminating the need for a dedicated ESR tube. Conclusion: Based on the consensus of the Working Group, recommendations for manufacturers for the validation of new ESR methods were developed. In addition, a list of recommendations for laboratories that are moving to modified or alternate methods was compiled, addressing instrument performance verification and commu- nications of results to clinical users. KEYWORDS erythrocyte sedimentation rate, laboratory hematology, laboratory standards, recommendations, westergren 1 | INTRODUCTION 1.1 | History of the erythrocyte sedimentation rate In many hematology laboratories, the erythrocyte sedimentation rate (ESR) is among the most frequently ordered tests. The pro- cedure was first described in 1894 by Dr. Edmund Biernacki, as well as independently thereafter by Drs. Hirszfeld, Fåhraeus, and Westergren. 1 It is based on the principle that the sedimentation of red cells in plasma provides a measure of the level of acute- phase proteins and therefore of inflammation. 2 While the test is not specific for any particular disease, it remains widely used for its clinical utility in establishing the diagnosis of several dis- eases, as well as monitoring the activity of selected inflammatory