Results between different clinical laboratory measurement procedures should be equivalent, within clinically meaningful limits, to enable optimal use of clinical guidelines for disease diagnosis and patient management. When laboratory test results are neither standardized nor harmonized, a different numeric result may be obtained for the same clinical sample. Unfortunately, some guidelines base decisions on test results from a specific laboratory measurement procedure without considering the possibility or likelihood of differences between various measurement procedures. When this happens, erroneous decisions will be made regarding a specific patient's care, and aggregation of data from different clinical research investigations will be flawed.

To address these issues, the AACC convened an international leadership forum in 2010, "Improving Clinical Laboratory Testing through Harmonization: An International Forum." The conference brought together 90 scientists, from 13 countries, representing laboratory, clinical, public health, metrology and regulatory organizations to establish a framework to improve harmonization of laboratory results for measurands that do not have reference measurement procedures.

The conference recommended that an infrastructure be created to coordinate worldwide efforts to harmonize or standardize measurands, to prioritize measurands in need of harmonization based on clinical impact, to evaluate technical feasibility for harmonization, and to either establish a work group to achieve harmonization for measurands or refer a particular measurand to an interested organization for harmonization. The harmonization process requires the involvement and collaboration of international clinical and medical organizations, IVD manufacturers, clinical laboratories, metrology institutes, public health organizations, standard setting organizations, and regulatory agencies.

The International Consortium for Harmonization of Clinical Laboratory Results was established to fulfil the recommendations from the conference. The governing body is a Council made up of organizations from around the world that contribute financially to support the administration of the program. A Harmonization Oversight Group (HOG) is responsible to manage the harmonization activities. Interested stakeholders may become Organizational Members who provide an intermediate level of financial support and appoint a member of the HOG, or become members of the Strategic Partners Group who submit measurands for harmonization, and nominate experts to serve on the HOG. The AACC is the secretariat for administration of the program.