By Anonymous on Friday, April 25, 2003 - 11:38 am:
How I calculate the inter assay between 2 laboratories and in the same lab but in different days?there is difference in the calculation?
By Tim on Monday, April 28, 2003 - 05:51 am:
There shouldn't be any difference in the way you do the calculation. The way we do them is to take the means for each component and they have to be within +/- 2% for major components (i.e. work out 98-102% for one mean and the other has to be within those limits). For low level components (degradates) that are normally calulcated as %, the limit we have is +/-2.5% relative if levels are >=1% (i.e. similar to above - mean of one is 97.5 - 102.5% of other) and +/-0.25% absolute for levels less than 1%. This all assumes you have good enough precision on your replicate samples