title: Quality control of phenotypic forms data in the Type 1 Diabetes Genetics Consortium.
abstract: BACKGROUND
  When collecting phenotypic data in clinics across the globe, the Type 1 Diabetes Genetics Consortium (T1DGC) used several techniques that ensured consistency, completeness, and accuracy of the data.
  
  
  OBJECTIVE
  The aim of this article is to describe the procedures used for collection, entry, processing, and management of the phenotypic data in this international study.
  
  
  METHODS
  The T1DGC ensured the collection of high quality data using the following procedures throughout the entire study period. The T1DGC used centralized and localized training, required a pilot study, certified all data entry personnel, created standardized data collection forms, reviewed a sample of form sets quarterly throughout the duration of the study, and used a data entry system that provided immediate feedback to those entering the data.
  
  
  RESULTS
  Due to the intensive procedures in developing the forms, the study was able to uphold consistency among all clinics and minimal changes were required after implementation of the forms. The train-the-trainer model was efficient and only a small number of clinics had to repeat a pilot study. The study was able to maintain a low percentage of missing data (<0.001%) and low duplicate data entry error rate (0.10%).
  
  
  CONCLUSIONS
  It is critical to provide immediate follow-up in order to reinforce training and ensure the quality of the data collected and entered.
authors.affiliation: Division of Public Health Sciences, Wake Forest University Health Sciences, Winston-Salem, NC 27157, USA. lperdue@wfubmc.edu
authors.forename: Letitia H
authors.initials: LH
authors.lastname: Perdue
authors.forename: Lotte
authors.initials: L
authors.lastname: Albret
authors.forename: Alan
authors.initials: A
authors.lastname: Aldrich
authors.forename: Amanda
authors.initials: A
authors.lastname: Loth
authors.forename: Elizabeth G
authors.initials: EG
authors.lastname: Sides
authors.forename: Angela
authors.initials: A
authors.lastname: Dove
authors.forename: Ana M
authors.initials: AM
authors.lastname: Wägner
authors.forename: Rebecca
authors.initials: R
authors.lastname: Waterman
authors.forename: June J
authors.initials: JJ
authors.lastname: Pierce
authors.forename: Beena
authors.initials: B
authors.lastname: Akolkar
authors.forename: Michael W
authors.initials: MW
authors.lastname: Steffes
authors.forename: Joan E
authors.initials: JE
authors.lastname: Hilner
mesh_terms: D035843:Biomedical Research / Q000458:organization & administration; D003625:Data Collection / Q000941:ethics / Q000379:methods*; D003922:Diabetes Mellitus, Type 1 / Q000235:genetics*; D014943:Global Health; D006801:Humans; D007258:Informed Consent; D038622:Internationality; D010641:Phenotype; D010865:Pilot Projects; D011786:Quality Control