title: Heterogeneity of manufacturers' declarations for lipemia interference--an urgent call for standardization.
abstract: BACKGROUND
  Due to the budget limitations, laboratories mostly rely on the manufacturers' information about the influence of interfering substances on laboratory results. However, some manufacturers do not follow the recommended procedures for testing interferences (CLSI standard) and there is a great variability in the presentation of data regarding lipemia interference.
  
  
  METHODS
  We aimed to verify the manufacturers' specifications for lipemia interference for clinical chemistry reagents provided by Beckman Coulter, Roche and Siemens. Bias was determined using the Intralipid® simulated lipemic samples. Furthermore, we aimed to compare obtained data with the manufacturers' claims and desirable specification for imprecision derived from biological variation.
  
  
  RESULTS
  i) Manufacturers' declarations were not confirmed for all three manufacturers; ii) the magnitude and direction of the effect of lipemia on laboratory results differ substantially between the three tested analytical systems; and iii) manufacturers are using arbitrary limits in declaring the expected effect of interference on laboratory results.
  
  
  CONCLUSIONS
  There is an urgent need to standardize the way manufacturers test and report their data on the lipemia interference. We propose that, instead of arbitrary limits, manufacturers use evidence based quality specifications for assessing the allowable biases. Moreover, laboratories should be aware of the possible lack of replicability of manufacturers' declarations.
authors: University Department of Chemistry, Medical School University Hospital Sestre Milosrdnice, Vinogradska 29, 10000 Zagreb, Croatia. Electronic address: nora.nikolac@gmail.com.
authors: Nora
authors: N
authors: Nikolac
authors: Ana-Maria
authors: AM
authors: Simundic
authors: Manuela
authors: M
authors: Miksa
authors: Gabriel
authors: G
authors: Lima-Oliveira
authors: Gian Luca
authors: GL
authors: Salvagno
authors: Beatrice
authors: B
authors: Caruso
authors: Gian Cesare
authors: GC
authors: Guidi
mesh_terms: D019963:Clinical Chemistry Tests / Q000592:standards*; D064790:Clinical Laboratory Services / Q000592:standards*; D006801:Humans; D006949:Hyperlipidemias / Q000097:blood*; D015203:Reproducibility of Results
keywords: Bias; CLSI; Clinical and Laboratory Standards Institute; DSI; Interferences; Lipemia; Preanalytical error; Quality specifications; desirable specification for imprecision