title: Establishing pediatric reference intervals for 13 biochemical analytes derived from normal subjects in a pediatric endocrinology clinic in Korea.
abstract: OBJECTIVE
  Defining pediatric reference intervals is one of the most difficult tasks for laboratory physicians. The continuously changing physiology of growing children makes their laboratory values moving targets. In addition, ethnic and behavioral differences might also cause variations. The aim of this study was to establish age- and sex-specific partitioned reference intervals for 13 serum biochemical analytes in Korean children.
  
  
  METHODS
  A total of 2474 patients, girls aged 2-14 years and boys aged 2-16 years, who underwent a short stature workup but were diagnosed as normal at the Pediatric Endocrinology Clinic of Severance Hospital (Seoul, Korea) between September 2010 and June 2012 were included in this study. The levels of serum calcium, inorganic phosphorus, blood urea nitrogen, creatinine, uric acid, glucose, total cholesterol, total protein, albumin, alkaline phosphatase, aspartic aminotransferase, alanine aminotransferase, and total bilirubin were measured using a Hitachi 7600 analyzer (Hitachi High-Technologies Corporation, Tokyo, Japan). Reference intervals were partitioned according to sex or age subgroups using the Harris and Boyd method.
  
  
  RESULTS
  Most analytes except calcium and albumin required partitioning either by sex or age. Age-specific partitioned reference intervals for alkaline phosphatase, creatinine, and total bilirubin were established for both males and females after being partitioned by sex. Additional age-specific partitioning of aspartic aminotransferase in females and total protein and uric acid in males was also required. Inorganic phosphorus, total cholesterol, alanine aminotransferase, blood urea nitrogen, and glucose were partitioned only by sex.
  
  
  CONCLUSIONS
  This study provided updated age- and sex-specific pediatric reference intervals for 13 basic serum chemistry analytes from a sufficient number of healthy children by using a modern analytical chemistry platform.
authors.affiliation: Department of Laboratory Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Sun-Mi
authors.initials: SM
authors.lastname: Cho
authors.affiliation: Department of Laboratory Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Sang-Guk
authors.initials: SG
authors.lastname: Lee
authors.affiliation: Department of Pediatrics, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Ho Seong
authors.initials: HS
authors.lastname: Kim
authors.affiliation: Department of Laboratory Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea. Electronic address: jeongho@yuhs.ac.
authors.forename: Jeong-Ho
authors.initials: JH
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D000367:Age Factors; D015415:Biomarkers / Q000097:blood*; D001774:Blood Chemical Analysis / Q000379:methods*; D002624:Chemistry, Clinical / Q000379:methods*; D002648:Child; D002675:Child, Preschool; D004704:Endocrinology; D005260:Female; D006776:Hospitals, Pediatric; D006801:Humans; D008297:Male; D012016:Reference Values; D056910:Republic of Korea; D012737:Sex Factors
chemical_list: D015415:Biomarkers
keywords: Partitioning; Pediatric; Reference interval