title: Impact of discrepant results from clinical laboratories on patients and pharmaceutical trials: evidence from proficiency testing results.
abstract: OBJECTIVE
  Despite improvements achieved in laboratory medicine over the years, discrepant results from different clinical laboratories are still a source of imminent risk to patients and the pharmaceutical industry. The problem is aggravated by a disconnection between laboratorians and clinicians or drug developers.
  
  
  METHODS
  In this report, results from proficiency testing, originally established as a tool for good laboratory practice, were used to highlight the size of the problem and its impact on patients and pharmaceutical trials. Results from three laboratory tests, believed to be standardized and commonly requested as tools in the management of patients, and decision-making biomarkers in drug development were used: prothrombin time expressed as international normalization ratio, digoxin and low-density lipoprotein-cholesterol.
  
  
  RESULTS
  Unfortunately, data demonstrate that results for the same sample or batch of samples, if analyzed by different laboratories or even by one laboratory that employs different platforms or reagents, can be extremely different.
  
  
  CONCLUSIONS
  In the absence of an effective laboratory-to-laboratory, method-to-method or platform-to-platform standardization, or at lowest harmonization of test results, laboratory results could be misleading to clinicians and the drug industry. Drug developers need to understand the current challenge before any attempt to use biomarker data to make decisions, compile data for a biomarker from different studies or use biomarkers to bridge between different drug candidates belonging to a particular class of compounds.
authors.affiliation: Daiichi Sankyo Pharma Development, 399 Thornall St., Edison, NJ 08837, USA. ahalim@dsi.com
authors.forename: Abdel-Baset
authors.initials: AB
authors.lastname: Halim