calculation of 90% CI for continuous variable in clinical endpoint studies [General Sta­tis­tics]

posted by GM – India, 2017-11-21 07:02 (2403 d 12:54 ago) – Posting: # 17995
Views: 5,010

Hello El-Maestro,

Sorry I am understanding the guidance (see Clindamycin OGD)wrongly, as I already told "am new to endpoint studies".

As per the OGD section #6, the primary end point is, Percent change from baseline to week 12 in the inflammatory (papules and pustules) lesion count.

As per the OGD section #20, Equivalence Analysis

The compound hypothesis to be tested is:
H0: µT / µR ≤ θ1 or µT / µR ≥ θ2 versus HA : θ1 < µT / µR < θ2

Where µT = mean of test treatment, and µR = mean of reference treatment
Typically, we reject H0 with a type I error α = 0.05 (two 1-sided tests), if the 90% confidence interval for the ratio of means between test and reference products (µT / µR) is contained within the interval [θ1, θ2], where θ1 = 0.80 and θ2 = 1.25.

Here as per my understanding, the primary endpoint is untransformed data. That's why I had this confusion:confused:. and why 90% CI interval given as 00.80-1.25?

if the primary endpoint is ln-transformed data then there is no problem to calculate ratio of means or difference of means as you said earlier.

Sorry if I am confusing everybody. Kindly give me some idea on this.

Thanks in advance,

Best Regards,

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