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

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,
GM
—
Best Regards,
GM
Best Regards,
GM
Complete thread:
- calculation of 90% CI for continuous variable in clinical endpoint studies GM 2017-11-17 04:55 [General Statistics]
- calculation of 90% CI for continuous variable in clinical endpoint studies ElMaestro 2017-11-18 21:17
- calculation of 90% CI for continuous variable in clinical endpoint studies GM 2017-11-19 12:13
- calculation of 90% CI for continuous variable in clinical endpoint studies ElMaestro 2017-11-20 20:41
- calculation of 90% CI for continuous variable in clinical endpoint studiesGM 2017-11-21 06:02
- calculation of 90% CI for continuous variable in clinical endpoint studies DavidManteigas 2017-11-21 10:01
- calculation of 90% CI for continuous variable in clinical endpoint studiesGM 2017-11-21 06:02
- calculation of 90% CI for continuous variable in clinical endpoint studies ElMaestro 2017-11-20 20:41
- calculation of 90% CI for continuous variable in clinical endpoint studies GM 2017-11-19 12:13
- calculation of 90% CI for continuous variable in clinical endpoint studies ElMaestro 2017-11-18 21:17