The reasons not to pool [Power / Sample Size]

posted by mittyri – Russia, 2016-08-29 00:05 (2740 d 22:28 ago) – Posting: # 16602
Views: 11,013

Dear Astea,

your questions seems to me rhetorical ;-)

❝ As I understand, pooling CV is a part of metha-analysis. In its turn meta-analysis conceals many suprises, Simpson's paradox as example.

We are pooling not the data sets, but some statistical parameters (pooled CVs), so Simpson's paradox is another story

❝ The question is how to make sure of homogenity of pooling data? What can be the reasons to throw out some outlier data, excluding Gut feeling?

You cannot be sure till the moment you have the CSR in your hands. Even then, I wouldn't be sure taking into account the quality of data management in some CRO. So the gut feeling weighting is the best.
By the way have you heard about pilot studies in Russia? I'm not

❝ Can we pool data from studies with different dosage or studies with different formulations? How do the strength of the dosage affects variability?

I think it depends on many things (PK linearity, sensitivity of the method).
I suppose you have a huge data base (may be even the best in Russia ;-) ), so you can analyze some trends by yourself. In my experience the IntraSCV is usually higher for low strengths (but not for all cases)

Kind regards,

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