meta analysis? [Regulatives / Guidelines]

posted by Ohlbe – France, 2010-08-07 01:21 (4798 d 08:38 ago) – Posting: # 5738
Views: 15,116

Dear Martin, dear all,

I'm not a statistician. But as a "lay person" my question would be: what do we need to demonstrate ? The problem raised by the assessor is not that one study shows bioequivalence but a previous study was inconclusive (that's the situation where there were discussions about meta analysis at some point in time, if I'm not mistaken). The problem is rather that there are fluctuations in the point estimates between different studies, and I'm not sure what new information a meta analysis will bring.

When reading the objection from the assessor, it seems to me that he/she is considering the point estimate to be a "true value", not an experimental value affected by some level of uncertainty. This is reflected in the statement "This fluctuation can not be explained through the "intra-subject variability" as the latter influences Cmax and hence justifies the widening of the acceptance range for Cmax but not the fluctuating point estimates which are independent of this variability. This fluctuation is also independent of the number of subjects in the studies". This statement is not correct: the number of subjects in your study will directly influence the "reliability" of your experimental determination of the point estimate. Particularly with a high intra-CV. Actually, that level of uncertainty is precisely what the confidence interval represents, isn't it ?

I would see two possible ways out:(And with a second thought, you can still use the end of the first option with the second option...)



Complete thread:

UA Flag
 Admin contact
22,759 posts in 4,775 threads, 1,628 registered users;
18 visitors (0 registered, 18 guests [including 8 identified bots]).
Forum time: 09:59 CEST (Europe/Vienna)

Whenever a theory appears to you as the only possible one,
take this as a sign that you have neither understood the theory
nor the problem which it was intended to solve.    Karl R. Popper

The Bioequivalence and Bioavailability Forum is hosted by
BEBAC Ing. Helmut Schütz