Intra Subject variabilty calculation

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Dear All, I am using the design like RR,RT1,RT2,T1T2,T1T1,T2T2 and objective is to find the ICV for R,T1 and T2,. Due to time constraints we can not go for higher period design. After running BE wizard I have got the following from Final varince Parameter sheet: Dependent Units Parameter Estimate Ln(AUCt) lambda(1,1)_11 0.452901932 Ln(AUCt) lambda(1,2)_11 0.467542526 Ln(AUCt) lambda(1,3)_11 0.544891068 Ln(AUCt) lambda(2,2)_11 5.36705E-07 Ln(AUCt) lambda(2,3)_11 2.88626E-07 Ln(AUCt) Var(PeriodForSubject)_21 0.03710071 Ln(AUCt) Var(PeriodForSubject)_22 0.038877323 Ln(AUCt) Var(PeriodForSubject)_23 0.03240041 So can any one tell me how to estimate ICV for R,T1 and T2 from Winnonlin. Thanks in advance Best Regards Ashwani

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Look at the “Parameter Key” output workbook, in the Parameter and the Group_Level columns, to determine which variance parameter is for the reference formulation and which are for the test formulations. If your formulations are called R, T1 and T2, then I think the order will be: Var(PeriodForSubject)_21 is for R, Var(PeriodForSubject)_22 is for T1, Var(PeriodForSubject)_23 is for T2. If that is the case, then the within-subject variances for R, T1, and T2 are: sigma_WR^2 = Var(PeriodForSubject)_21 sigma_WT1^2 = Var(PeriodForSubject)_22 sigma_WT2^2 = Var(PeriodForSubject)_23 The intra-subject CV’s can be computed as: IntraCV_R = 100%*sqrt(exp(sigma_WR^2)-1) and similarly for T1 and T2. If you want to upload your project, I can look at this further. Linda

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Dear Linda,

Thanks for prompt reponse.

As my objective is to estinate ICV of R , T1 & T2 and to check BE between these formutaltion.
Kindly note this is pilot trial.

I have attached the complete projects for your considerations.

wiating for your response.

Thanks in advance
ashwani.marwah@biocon.com
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interpretation of the following:

Dependent Units Parameter Estimate Interpretation ICV
Ln(AUCt) lambda(1,1)_11 0.492489325
Ln(AUCt) lambda(1,2)_11 0.499867677
Ln(AUCt) lambda(1,3)_11 0.586652582
Ln(AUCt) lambda(2,2)_11 1.88352E-08
Ln(AUCt) lambda(2,3)_11 1.02701E-08
Ln(AUCt) Var(PeriodForSubject)_21 0.037145905
Ln(AUCt) Var(PeriodForSubject)_22 0.039695745
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Hello Ashwani, I looked at your project and the formulations were in the order I thought on tthe Parameter Key output - first R, then T1, then T2. So you can estimate the intra-subject CV (also called ICV or intra-individual CV) as: Intra-subject CV for R = 100 * sqrt[ exp( Var(PeriodForSubject)_21 ) - 1] Intra-subject CV for T1 = 100 * sqrt[ exp( Var(PeriodForSubject)_22 ) - 1] Intra-subject CV for T2 = 100 * sqrt[ exp( Var(PeriodForSubject)_23 ) - 1] Var(PeriodForSubject)_21 is the intra-subject variance for R, sigma_WR^2.