title: Advantages of collecting multiple urinary iodine concentrations when assessing iodine status of a population.
abstract: OBJECTIVE
  To evaluate the effect of collecting multiple (four) urine samples on the extensive variance often observed within a cohort when determining iodine status via urinary iodine concentration (UIC).
  
  
  METHODS
  Fifty-one children aged two to three years and thirty children aged 8-10 years participated in the study in South East Queensland, Australia. Each child's four urine samples were analysed using ammonium persulphate digestion before a Sandell-Kolthoff reaction method. Analysis of variance techniques were used to assess the effect of using multiple urine samples.
  
  
  RESULTS
  The median UICs were 223.3 and 141 μg/L for two- to three-year-olds and eight- to 10-year-olds, respectively. The coefficient of variance (CV) of UIC for children aged two to three years was reduced by 35.6%, 36.5% and 39.7% when two, three and four samples were included in the adjustment, respectively. Similarly, the CV of UIC for children aged 8-10 years was reduced by 24.7%, 30.7% and 34.7%, respectively.
  
  
  CONCLUSIONS
  Although the practicality and cost of collecting multiple UICs need to be considered, collecting multiple UIC samples from each participant provides a more accurate reflection of a cohort iodine status.
authors: Children's Nutrition Research Centre, Child Health Research Centre, The University of Queensland, Herston, QLD, Australia.|School of Medicine, The University of Queensland, Herston, QLD, Australia.
authors: A J
authors: AJ
authors: Samidurai
authors: Child Health Research Centre, School of Medicine, The University of Queensland, Herston, QLD, Australia.|Queensland Children's Medical Research Institute, Herston, QLD, Australia.|School of Public Health, The University of Queensland, Herston, QLD, Australia.
authors: R S
authors: RS
authors: Ware
authors: Children's Nutrition Research Centre, Child Health Research Centre, The University of Queensland, Herston, QLD, Australia.|School of Medicine, The University of Queensland, Herston, QLD, Australia.
authors: P S W
authors: PS
authors: Davies
mesh_terms: D002648:Child; D002675:Child, Preschool; D005260:Female; D006304:Health Status; D006801:Humans; D007455:Iodine / Q000652:urine*; D008297:Male; D016482:Urinalysis / Q000379:methods* / Q000706:statistics & numerical data
chemical_list: D007455:Iodine
keywords: Children; Iodine; Iodine status surveillance; Urinary iodine concentration