Page 54 - Quality control of pharmaceuticals (07-PA 704)
P. 54
Calculation of precision parameter Levels:-
a) Repeatability:
It is assessed by: (1) at least 6 replicates of 100% test concentration or (2) by 3
determinations of different concentrations, 3 replicates each.
Example (3):
Comment on the precision of the following data obtained from 6 experiments of
solutions containing 100% test concentration:
Experiment No. % Found
1 100.5
2 99.9
3 101.9
4 101.3
5 99.8
6 99.3
Mean = 100.45
S = 0.9874
RSD = (CV%) = (0.9874 × 100.45) × 100 = 0.98%
Acceptance limit: RSD % less than 2%
Conclusion:
Since the coefficient of variation less than 2%. The results having good
repeatability.
Comment on the precision of the data present in example (2)
b) Intermediate precision:
This expresses within-laboratories variations.
