Performance characteristics of six XXXX assays.

@entity407 @entity5377 @entity1087 @entity1255 @entity5784 @entity74 @entity2142
Elevated concentrations of @entity1255 ( @entity5784 ) are associated with a @entity74 . Linearity, imprecision, interference, method comparison, and accuracy were evaluated on the ADVIA Centaur ( @entity5377 Healthcare Diagnostics, Deerfield, IL), ARCHITECT i2000SR (Abbott Diagnostics, Abbott Park, IL), AxSYM (Abbott Diagnostics), and IMMULITE 2000 ( @entity5377 Healthcare Diagnostics) methods and analyzers and the Catch (Equal Diagnostics, Exton, PA) and Diazyme (Diazyme Laboratories, San Diego, CA) methods, both on the Modular P analyzer (Roche Diagnostics, Indianapolis, IN). All methods were linear with maximum deviations from target recoveries of less than 10%. Total coefficients of variation ranged from 1.7% to 9.4%. The effects of @entity2142 , @entity1087 , and @entity407 were assessed. Method comparisons were performed using high-performance liquid chromatography as the comparison method. Correlation coefficients were 0.95 to 0.99. Bland-Altman plots demonstrated percentage bias of -29.3% (IMMULITE) to 7.2% (Centaur). Accuracy using the National Institute of Standards and Technology Standard Reference Material 1955 showed varying results with only 1 method within the certified range for all 3 levels. All methods demonstrated acceptable performance except the IMMULITE, which is less precise and accurate. Standardization of most methods seems acceptable, although continuing efforts are warranted.
