title: The Asian project for collaborative derivation of reference intervals: (1) strategy and major results of standardized analytes.
abstract: BACKGROUND
  A multicenter study conducted in Southeast Asia to derive reference intervals (RIs) for 72 commonly measured analytes (general chemistry, inflammatory markers, hormones, etc.) featured centralized measurement to clearly detect regionality in test results. The results of 31 standardized analytes are reported, with the remaining analytes presented in the next report.
  
  
  METHODS
  The study included 63 clinical laboratories from South Korea, China, Vietnam, Malaysia, Indonesia, and seven areas in Japan. A total of 3541 healthy individuals aged 20-65 years (Japan 2082, others 1459) were recruited mostly from hospital workers using a well-defined common protocol. All serum specimens were transported to Tokyo at -80°C and collectively measured using reagents from four manufacturers. Three-level nested ANOVA was used to quantitate variation (SD) of test results due to region, sex, and age. A ratio of SD for a given factor over residual SD (representing net between-individual variations) (SDR) exceeding 0.3 was considered significant. Traceability of RIs was ensured by recalibration using value-assigned reference materials. RIs were derived parametrically.
  
  
  RESULTS
  SDRs for sex and age were significant for 19 and 16 analytes, respectively. Regional difference was significant for 11 analytes, including high density lipoprotein (HDL)-cholesterol and inflammatory markers. However, when the data were limited to those from Japan, regionality was not observed in any of the analytes. Accordingly, RIs were derived with or without partition by sex and region.
  
  
  CONCLUSIONS
  RIs applicable to a wide area in Asia were established for the majority of analytes with traceability to reference measuring systems, whereas regional partitioning was required for RIs of the other analytes.
authors: Department of Clinical Laboratory Sciences, Faculty of Health Sciences, Yamaguchi University Graduate School of Medicine, Minami-Kogushi 1-1-1, Ube, 755-8505 Japan. ichihara@yamaguchi-u.ac.jp
authors: Kiyoshi
authors: K
authors: Ichihara
authors: Ferruccio
authors: F
authors: Ceriotti
authors: Tran Huu
authors: TH
authors: Tam
authors: Shigeo
authors: S
authors: Sueyoshi
authors: Priscilla M K
authors: PM
authors: Poon
authors: Mee Ling
authors: ML
authors: Thong
authors: Yasushi
authors: Y
authors: Higashiuesato
authors: Xuejing
authors: X
authors: Wang
authors: Hiromi
authors: H
authors: Kataoka
authors: Akemi
authors: A
authors: Matsubara
authors: Shu-Chu
authors: SC
authors: Shiesh
authors: Dewi
authors: D
authors: Muliaty
authors: Jeong-Ho
authors: JH
authors: Kim
authors: Masakazu
authors: M
authors: Watanabe
authors: Christopher W K
authors: CW
authors: Lam
authors: Lothar
authors: L
authors: Siekmann
authors: Joseph B
authors: JB
authors: Lopez
authors: Mauro
authors: M
authors: Panteghini
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000704:Analysis of Variance; D044466:Asian People; D016207:Cytokines / Q000097:blood / Q000592:standards*; D004573:Electrolytes / Q000097:blood / Q000592:standards*; D004798:Enzymes / Q000097:blood / Q000592:standards*; D005260:Female; D042341:Gonadal Hormones / Q000097:blood / Q000592:standards*; D006801:Humans; D007136:Immunoglobulins / Q000097:blood*; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012737:Sex Factors
chemical_list: D016207:Cytokines; D004573:Electrolytes; D004798:Enzymes; D042341:Gonadal Hormones; D007136:Immunoglobulins