Ichihara, KiyoshiBarth, Julian HKlee, GeorgeQiu, LingErasmus, Rajiv RajivBorai, AnwarEvgina, SvetlanaAshavaid, TesterKhan, DilshadSchreier, LauraRolle, ReynanShimizu, YoshihisaKimura, ShogoKawano, ReoArmbruster, DavidMori, KazuoYadav, Binod Binod2022-11-032022-11-032017-04Ichihara, K. vd. (2017). ''A global multicenter study on reference values: 1. Assessment of methods for derivation and comparison of reference intervals''. Clinica Chimica Acta, 467(Special Issue), 70-82.0009-89811873-3492https://doi.org/10.1016/j.cca.2016.09.016https://www.sciencedirect.com/science/article/pii/S0009898116303886http://hdl.handle.net/11452/29335Objectives: The IFCC Committee on Reference Intervals and Decision Limits coordinated a global multicenter study on reference values (RVs) to explore rational and harmonizable procedures for derivation of reference intervals (Rls) and investigate the feasibility of sharing RIs through evaluation of sources of variation of RVs on a global scale. Methods: For the common protocol, rather lenient criteria for reference individuals were adopted to facilitate harmonized recruitment with planned use of the latent abnormal values exclusion (LAVE) method. As of July 2015, 12 countries had completed their study with total recruitment of 13,386 healthy adults. 25 analytes were measured chemically and 25 immunologically. A serum panel with assigned values was measured by all laboratories. Rls were derived by parametric and nonparametric methods. Results: The effect of LAVE methods is prominent in analytes which reflect nutritional status, inflammation and muscular exertion, indicating that inappropriate results are frequent in any country. The validity of the parametric method was confirmed by the presence of analyte-specific distribution patterns and successful Gaussian transformation using the modified Box-Cox formula in all countries. After successful alignment of RVs based on the panel test results, nearly half the analytes showed variable degrees of between-country differences. This finding, however, requires confirmation after adjusting for BMI and other sources of variation. The results are reported in the second part of this paper. Conclusion: The collaborative study enabled us to evaluate rational methods for deriving Rls and comparing the RVs based on real-world datasets obtained in a harmonized manner.eninfo:eu-repo/semantics/openAccessMedical laboratory technologyReference intervalsMulticenter studyLatent abnormal values exclusion methodHarmonizationStandardizationStandard deviation ratioSerum panelModified Box-Cox power transformationEthnic differencesReference preparation crm470Common biochemical analytes6 asian citiesCollaborative derivationWorldwide multicenterReference individualsSerumPlasmaStrategyTestsClinical laboratory techniquesHealthy volunteersHumansInternationalityNormal distributionReference valuesArticle0004023527000122-s2.0-850462365017082467Special Issue27666761Medical laboratory technologyClinical Chemistry; Thyrotropin; Chemical SpeciesAdultAgedAnalytic methodArticleBody massData analysisEthnic differenceFeasibility studyFemaleHumanInflammationLaboratory testLatent abnormal values exclusionMaleMuscle exerciseNormal distributionNormal humanNutritional statusReference valueStandardizationValidityClinical trialInternational cooperationLaboratory techniqueMulticenter studyNeference valueStandards