title: Comparison of the 99th percentiles of three troponin I assays in a large reference population.
abstract: BACKGROUND
  The IFCC Task Force on Clinical Applications of Cardiac Biomarkers suggests comparing several contemporary sensitive troponin assays in the same, sufficiently large reference population.
  
  
  METHODS
  Three contemporary sensitive assays were used to measure troponin I concentration in samples from a uniquely large healthy population (2404 individuals) and in a sub-group with tighter inclusion criteria of 908 individuals. The 99th percentiles were calculated using quantile regression which takes the entire population into account.
  
  
  RESULTS
  The 99th percentile for the ARCHITECT STAT Troponin I assay was 21 ng/L, 31 ng/L for the ADVIA Centaur Troponin I-Ultra assay and 28 ng/L for the Dimension Vista cTnI assay. Significantly higher values were found in males than in women only in the Dimension Vista cTnI assay and in the subgroup for the ARCHITECT STAT Troponin I assay.
  
  
  CONCLUSIONS
  Quantile regression provides a tool to accurately estimate the 99th percentile and establish a continuous function of the relation between the 99th percentile and the age and gender. There was no age dependency demonstrated. A gender difference was found in one assay but inconclusive in another and not demonstrated in a third.
authors.forename: Astrid
authors.initials: A
authors.lastname: Petersmann
authors.forename: Till
authors.initials: T
authors.lastname: Ittermann
authors.forename: Cornelia
authors.initials: C
authors.lastname: Fries
authors.forename: Norbert
authors.initials: N
authors.lastname: Lubenow
authors.forename: Thomas
authors.initials: T
authors.lastname: Kohlmann
authors.forename: Anders
authors.initials: A
authors.lastname: Kallner
authors.forename: Andreas
authors.initials: A
authors.lastname: Greinacher
authors.forename: Matthias
authors.initials: M
authors.lastname: Nauck
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D019411:Clinical Laboratory Techniques / Q000592:standards*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012737:Sex Factors; D019210:Troponin I / Q000032:analysis*; D055815:Young Adult
chemical_list: D019210:Troponin I