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Requirements for the ‘top-down’ approach to evaluating uncertainty

The best available estimate of method precision

  • obtained from validation studies (including collaborative studies) or ongoing quality control;
  • a parameter varied representatively during a precision experiment requires no further study to evaluate the uncertainty.

The best available estimate of bias and its uncertainty.

Evaluation of any significant effects not covered by the precision and bias estimates

  • obtained by experiment, or from existing data.

Last modified on 02 February 2009.