title: Pediatric-specific reference intervals in a nationally representative sample of Iranian children and adolescents: the CASPIAN-III study.
abstract: BACKGROUND
  This study aimed to determine for the first time the age- and gender-specific reference intervals for biomarkers of bone, metabolism, nutrition, and obesity in a nationally representative sample of the Iranian children and adolescents.
  
  
  METHODS
  We assessed the data of blood samples obtained from healthy Iranian children and adolescents, aged 7 to 19 years. The reference intervals of glucose, lipid profile, liver enzymes, zinc, copper, chromium, magnesium, and 25-hydroxy vitamin D [25(OH)D] were determined according to the Clinical & Laboratory Standards Institute C28-A3 guidelines. The reference intervals were partitioned using the Harris-Boyd method according to age and gender.
  
  
  RESULTS
  The study population consisted of 4800 school students (50% boys, mean age of 13.8 years). Twelve chemistry analyses were partitioned by age and gender, displaying the range of results between the 2.5th to 97.5th percentiles. Significant differences existed only between boys and girls at 18 to 19 years of age for low density lipoprotein-cholesterol. 25(OH)D had the only reference interval that was similar to all age groups and both sexes.
  
  
  CONCLUSIONS
  This study presented the first national database of reference intervals for a number of biochemical markers in Iranian children and adolescents. It is the first report of its kind from the Middle East and North Africa. The findings underscore the importance of providing reference intervals in different ethnicities and in various regions.
authors.affiliation: Department of Pediatrics, Child Growth and Development Research Center, Research Institute for Primordial Prevention of Non Communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Roya
authors.initials: R
authors.lastname: Kelishadi
authors.affiliation: Biomedical Engineering Department, Engineering Faculty, the University of Isfahan, Isfahan, Iran.
authors.forename: Hamid Reza
authors.initials: HR
authors.lastname: Marateb
authors.affiliation: Department of Pediatrics, Child Growth and Development Research Center, Research Institute for Primordial Prevention of Non Communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran. j_mansourian@hlth.mui.ac.ir.|Department of biostatistics and Epidemiology, Health school, Isfahan University of Medical Sciences, Isfahan, 81745, Iran. j_mansourian@hlth.mui.ac.ir.
authors.forename: Marjan
authors.initials: M
authors.lastname: Mansourian
authors.affiliation: Department of Pediatrics, Child Growth and Development Research Center, Research Institute for Primordial Prevention of Non Communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Gelayol
authors.initials: G
authors.lastname: Ardalan
authors.affiliation: Epidemiology Department, Chronic Diseases Research Centre, Endocrinology and Metabolism Population Sciences Institute, Endocrinology and Metabolism Research Institute, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Ramin
authors.initials: R
authors.lastname: Heshmat
authors.affiliation: The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Khosrow
authors.initials: K
authors.lastname: Adeli
mesh_terms: D000293:Adolescent; D000367:Age Factors; D015415:Biomarkers / Q000097:blood*; D001774:Blood Chemical Analysis; D001842:Bone and Bones / Q000378:metabolism*; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007492:Iran; D008297:Male; D009752:Nutritional Status; D009765:Obesity / Q000097:blood*; D012015:Reference Standards; D015203:Reproducibility of Results; D012494:Sampling Studies; D012737:Sex Factors; D055815:Young Adult
chemical_list: D015415:Biomarkers
keywords: adolescents; biomarkers; chemistry; pediatrics; reference intervals