Precision

Repeatability.ICH definition: Repeatabilityexpresses the precision under the

same operating conditions over a short interval of time. Repeatability is also

termed intraassay precision.

Repeatability of a method can be determined by multiple replicate preparations

of the same sample. This can be done either by multiple sample preparations

(n = 6) in the same experiment or by preparing three replicates at three different

concentrations. In general, one should evaluate results of individual related sub-

stances, total related substances, and the consistency of related substance profiles

in all experiments. The percent RSD and confidence level of these results are

reported to illustrate the method repeatability.