## 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,

As per the OGD section #20, Equivalence Analysis

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 < θ2H0: 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

—

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