title: Allowable Total Error and Limits for Erroneous Results (ATE/LER) zones for agreement measurement.
abstract: BACKGROUND
  When assessing the agreement of two methods, the simple correlation coefficient, the most frequently used but easy to cause misleading interpretation of results, is still comprehensively adopted in journals of clinical chemistry or diagnostic laboratory. This study is aimed at comparing the correlation coefficient with the alternative method, which came from FDA recommended guidance for waiver assays--Allowable Total Error (ATE)/Limits for Erroneous Results (LER) zones, and fully addressing the applicable conditions of the later one.
  
  
  METHODS
  The data we use were both real and simulated data to calculate correlation coefficient and ATE/LER zones, respectively, when assessing the agreement. And a modified ATE/LER zones method was brought forward to assess the agreement of repeated measurements and the repeatability of each single method.
  
  
  RESULTS
  The high correlation can only indicate that the two methods are linearly related rather than in agreement with each other. However, the ATE/LER zones can avoid this shortcoming by using certain statistical strategies considering the clinical judgment. The modified method is suitable to evaluate the repeatability of single method and the agreement of repeated measurement by two measuring methods.
  
  
  CONCLUSIONS
  The ATE/LER zones method is a relatively reasonable and widely considering method for assessing the agreement.
authors: Department of Health Statistics, Second Military Medical University, Shanghai, China.
authors: Yu-Hao
authors: YH
authors: Zhou
authors: Jia-Jie
authors: JJ
authors: Zang
authors: Mei-Jing
authors: MJ
authors: Wu
authors: Jin-Fang
authors: JF
authors: Xu
authors: Jia
authors: J
authors: He
mesh_terms: D000230:Adenocarcinoma / Q000097:blood / Q000175:diagnosis; D019411:Clinical Laboratory Techniques / Q000592:standards*; D003951:Diagnostic Errors / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000175:diagnosis; D015203:Reproducibility of Results; D013223:Statistics as Topic
chemical_list: D017430:Prostate-Specific Antigen