BE study designs [Design Issues]
Dear Essar,
in order to continue with the nomenclature generally used in BE studies I have re-aranged your table. Periods (P1-P3) in columns, and Sequences/Groups (S1-S3) in rows:
Question #1: no
Question #2: yes
Yes, explanations following:
Your design is not balanced in respect to all effects in the model, in other words, 3 combinations of treatments are missing. The chance of regulatory acceptance of a 3×3 is close to zero.
The plainest design you may apply is a Williams' design (3-treatment, 3-period, 6-sequence):
If you want to extract paired comparisons (e.g., for the nonparametric method) you will fail with your design (3×3), but succeed with the given one (6×3).
Since we are leaving the novice's level now, I would suggest you some further reading (not cheap, but every cent worth):
Have a look at
Good Luck!
in order to continue with the nomenclature generally used in BE studies I have re-aranged your table. Periods (P1-P3) in columns, and Sequences/Groups (S1-S3) in rows:
┌────┬────────────┐
│ │ P1 P2 P3 │
├────┼────────────┤
│ S1 │ T1 T2 R │
│ S2 │ T2 R T1 │
│ S3 │ R T1 T2 │
└────┴────────────┘
❝ Now, please let me know whether my design is right? Is it approprirate to name this study as "3-treatment, 3-period, 3-sequence crossover Bioequivalence study"?
Question #1: no
Question #2: yes
❝ Can there be other designs to compare T1 and T2 with R in a single BE study?
Yes, explanations following:
Your design is not balanced in respect to all effects in the model, in other words, 3 combinations of treatments are missing. The chance of regulatory acceptance of a 3×3 is close to zero.
The plainest design you may apply is a Williams' design (3-treatment, 3-period, 6-sequence):
┌────┬────────────┐
│ │ P1 P2 P3 │
├────┼────────────┤
│ S1 │ T1 T2 R │
│ S2 │ T2 R T1 │
│ S3 │ R T1 T2 │
│ S4 │ T1 R T2 │
│ S5 │ T2 T1 R │
│ S6 │ R T2 T1 │
└────┴────────────┘
If you want to extract paired comparisons (e.g., for the nonparametric method) you will fail with your design (3×3), but succeed with the given one (6×3).
Since we are leaving the novice's level now, I would suggest you some further reading (not cheap, but every cent worth):
- B Jones and MG Kenward
Design and Analysis of Cross-Over Trials
Chapman & Hall, Boca Raton, (2nd Ed 2003)
- S-C Chow and J-p Liu
Design and Analysis of Bioavailability and Bioequivalence Studies
Marcel Dekker, New York, (2nd Ed 2000)
❝ Also, please let me know how you calculate the no of subjects required for this type of a study.
Have a look at
RP Qu
Sample Size and Power Calculation for High Order Crossover Design
Bio/Pharma Quarterly 9(1), 9-14 (March 2003)
which is available online (277kB PDF).
Good Luck!
Complete thread:
- BE study designs Essar 2006-01-12 04:47
- BE study designs Helmut 2006-01-12 18:38
- BE study designs Essar 2006-01-13 04:40
- BE study designs Essar 2006-01-16 13:20
- BE study designsHelmut 2006-01-16 15:39
- BE study designs Essar 2006-01-17 04:53
- BE study designs Helmut 2006-01-17 09:27
- BE study designs nguyenvo 2006-04-30 21:40
- sample size reference Helmut 2006-05-01 11:59
- BE study designs olacy 2006-06-23 09:28
- Reference (direct link) Helmut 2006-06-24 12:45
- BE study designs Essar 2006-01-17 04:53
- BE study designsHelmut 2006-01-16 15:39
- BE study designs shiv 2006-01-25 06:46
- ANVISA?! Helmut 2006-01-25 13:37
- BE study designs Helmut 2006-01-12 18:38