title: Test 1 analyser for determination of ESR. 1. Practical evaluation and comparison with the Westergren technique.
abstract: BACKGROUND
  various modifications of the Erythrocyte Sedimentation Rate (ESR) determination have been suggested since the original Westergren procedure that has been adopted as the gold standard by the International Council for Standardization in Haematology (ICSH). Recently, an automated method, (Alifax Test 1), based on a technique completely different from Westergren, has been introduced.
  
  
  METHODS
  In this comparative study, ESR of blood from 680 patients with various rheumatic diseases was determined on both Test 1 and the StaRRsed automated ESR analyser which performs measurements in accordance with ICSH specifications. Furthermore the robustness of the new technique was evaluated.
  
  
  RESULTS
  Direct correlation of Test 1 and StaRRsed measurements confirmed the results of previous studies: an overall correlation coefficient of R = 0.90. However, further statistical analysis showed that, depending on the instrument that was used, in 78 samples (i.e. 11.5%) the results could lead to different treatment suggestions. Furthermore it appeared that several procedural factors could influence the final Test 1 outcome.
  
  
  CONCLUSIONS
  Due to its sensitivity for procedural variations, Test 1 measurements should be carried out under strictly standardized conditions. Especially at the higher ESR levels the Test 1 technique is, however, not a reliable alternative for the ICSH approved 'Westergren' method.
authors.affiliation: Department of Translational Physiology, Academic Medical Center, Amsterdam, the Netherlands. mrhardeman@hotmail.com
authors.forename: Max R
authors.initials: MR
authors.lastname: Hardeman
authors.forename: Marieke
authors.initials: M
authors.lastname: Levitus
authors.forename: Antonio
authors.initials: A
authors.lastname: Pelliccia
authors.forename: Anna A
authors.initials: AA
authors.lastname: Bouman
mesh_terms: D057205:Automation, Laboratory / Q000295:instrumentation; D001799:Blood Sedimentation; D006403:Hematologic Tests / Q000295:instrumentation* / Q000379:methods; D006801:Humans; D012015:Reference Standards; D012216:Rheumatic Diseases / Q000097:blood; D012680:Sensitivity and Specificity