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Dear HS, thanks
Yes. It is a cross-over design for pilot be of 12 subjects.
Please find below data for Tmax of a drug XXX and suggest. I have used proc glm for this and here MSE_Sub(seq) is less than MSE_residual so inter subject CV% can not be calculated. This is practical data obtained. Please let me know that which kind of conclusion should be made on the basis of this data. Same thing happened in the data of Cmax where %CV_inter < %CV_intra.
Please discuss as so many of new comers in the feild might be facing this kind of problem.
Thanks in advance.
Stat_BE
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Edit: Tabs removed from table; original quotes restored (see here). [HS]
❝ So you are talking about a cross-over design.
Yes. It is a cross-over design for pilot be of 12 subjects.
❝ Yes, this is the rule. In a cross-over design the PK responses within a particular subject are compared (between occasions).
❝ I hardly can imaginge a situation where variability between subjects (i.e., Brown vs Blair) is lower than within a subjecti.e., Brown on day 1 vs Brown on day 2). Although theoretical possible from a statistical point of view, such a behaviour is counterintuitive, and IMHO not a single case is described in the literature.
❝ BTW, the expectation of CVintra < CVinter leads to the general preference of cross-over designs over parallel designs in BE studies.
Please find below data for Tmax of a drug XXX and suggest. I have used proc glm for this and here MSE_Sub(seq) is less than MSE_residual so inter subject CV% can not be calculated. This is practical data obtained. Please let me know that which kind of conclusion should be made on the basis of this data. Same thing happened in the data of Cmax where %CV_inter < %CV_intra.
Sub Seq Tmax_P-I Tmax_P-II
1 BA 3.50 2.50
2 BA 1.50 3.00
3 AB 2.50 5.00
4 AB 3.50 2.50
5 BA 5.00 2.50
6 AB 2.50 2.50
7 AB 2.50 2.50
8 BA 3.00 4.50
9 BA 4.00 4.00
10 AB 1.50 2.00
11 BA 2.50 3.00
12 AB 3.00 3.00Please discuss as so many of new comers in the feild might be facing this kind of problem.
Thanks in advance.
Stat_BE
--
Edit: Tabs removed from table; original quotes restored (see here). [HS]
Complete thread:
- can inter sub CV% > intra sub CV%? stat_be 2007-09-27 13:15 [Power / Sample Size]
![[Mix]](https://static.bebac.at/img/mix.png "open in Mix view")
- CVinter > CVintra! Helmut 2007-09-27 13:34
- CVinter > CVintra!stat_be 2007-10-03 07:35
- CVinter > CVintra! Ohlbe 2007-10-03 10:04
- ANOVA not for Tmax! Helmut 2007-10-03 15:02
- CVinter > CVintra! Helmut 2007-10-15 16:15
- CVinter > CVintra! stat_be 2007-10-16 12:19
- CVinter > CVintra! Helmut 2007-10-16 13:15
- CVinter > CVintra! krishna 2012-11-30 05:46
- WinNonlin random vs. fixed model Helmut 2012-11-30 13:54
- CVinter > CVintra! stat_be 2007-10-16 12:19
- CVinter > CVintra! Ohlbe 2007-10-03 10:04
- CVinter > CVintra!stat_be 2007-10-03 07:35
- CVinter > CVintra! Helmut 2007-09-27 13:34
Ing. Helmut Schütz