title: Methods, quality control and specimen management in an international multicentre investigation of type 1 diabetes: TEDDY.
abstract: BACKGROUND
  The vast array and quantity of longitudinal samples collected in The Environmental Determinants of Diabetes in the Young study present a series of challenges in terms of quality control procedures and data validity. To address this, pilot studies have been conducted to standardize and enhance both biospecimen collection and sample obtainment in terms of autoantibody collection, stool sample preservation, RNA, biomarker stability, metabolic biomarkers and T-cell viability.
  
  
  METHODS
  The Environmental Determinants of Diabetes in the Young is a multicentre, international prospective study (n = 8677) designed to identify environmental triggers of type 1 diabetes (T1D) in genetically at-risk children from ages 3 months until 15 years. The study is conducted through six primary clinical centres located in four countries.
  
  
  RESULTS
  As of May 2012, over three million biological samples and 250 million total data points have been collected, which will be analysed to assess autoimmunity status, presence of inflammatory biomarkers, genetic factors, exposure to infectious agents, dietary biomarkers and other potentially important environmental exposures in relation to autoimmunity and progression to T1D.
  
  
  CONCLUSIONS
  Detailed procedures were utilized to standardize both data harmonization and management when handling a large quantity of longitudinal samples obtained from multiple locations. In addition, a description of the available specimens is provided that serve as an invaluable repository for the elucidation of determinants in T1D focusing on autoantibody concordance and harmonization, transglutaminase autoantibody, inflammatory biomarkers (T-cells), genetic proficiency testing, RNA lab internal quality control testing, infectious agents (monitoring cross-contamination, virus preservation and nasal swab collection validity) and HbA1c testing.
authors.affiliation: Pediatrics Epidemiology Center, Morsani College of Medicine, University of South Florida, Tampa, FL, USA.
authors.forename: Kendra
authors.initials: K
authors.lastname: Vehik
authors.forename: Steven W
authors.initials: SW
authors.lastname: Fiske
authors.forename: Chad A
authors.initials: CA
authors.lastname: Logan
authors.forename: Daniel
authors.initials: D
authors.lastname: Agardh
authors.forename: Corrado M
authors.initials: CM
authors.lastname: Cilio
authors.forename: William
authors.initials: W
authors.lastname: Hagopian
authors.forename: Olli
authors.initials: O
authors.lastname: Simell
authors.forename: Merja
authors.initials: M
authors.lastname: Roivainen
authors.forename: Jin-Xiong
authors.initials: JX
authors.lastname: She
authors.forename: Thomas
authors.initials: T
authors.lastname: Briese
authors.forename: Sami
authors.initials: S
authors.lastname: Oikarinen
authors.forename: Heikki
authors.initials: H
authors.lastname: Hyoty
authors.forename: Anette-G
authors.initials: AG
authors.lastname: Ziegler
authors.forename: Marian
authors.initials: M
authors.lastname: Rewers
authors.forename: Ake
authors.initials: A
authors.lastname: Lernmark
authors.forename: Beena
authors.initials: B
authors.lastname: Akolkar
authors.forename: Jeffrey P
authors.initials: JP
authors.lastname: Krischer
authors.forename: Brant R
authors.initials: BR
authors.lastname: Burkhardt
mesh_terms: D000293:Adolescent; D001323:Autoantibodies / Q000097:blood; D018070:Biological Specimen Banks / Q000458:organization & administration* / Q000592:standards*; D002648:Child; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000235:genetics / Q000473:pathology*; D005243:Feces / Q000821:virology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008137:Longitudinal Studies; D011786:Quality Control; D012333:RNA, Messenger / Q000032:analysis; D013048:Specimen Handling / Q000379:methods* / Q000592:standards*
chemical_list: D001323:Autoantibodies; D012333:RNA, Messenger
keywords: RNA; T-cell viability; biomarker stability; data integrity; metabolic biomarkers; quality control; stool sample preservation