Abstract:
:The two-period cross-over design with two sequences of drug administration is a standard experimental design when bioequivalence of one test formulation is to be assessed in comparison with a reference formulation. Previously, an approach based on Fieller's confidence interval has been presented for the assessment of average bioequivalence under this particular design. However, the two-sequence two-period cross-over design is not very useful in the presence of unequal carry-over effects. Besides, this basic design does not provide independent estimators for the intra-subject variabilities. To overcome these limitations, it might be of interest to consider a higher-order cross-over design in which the number of periods and/or the number of sequences is greater than the number of formulations to be compared. Because of this, the present communication will concentrate on the generalization of Fieller's confidence interval concept for a particular group of higher-order cross-over designs. In addition to this, since the evaluation of simple average bioequivalence does not guarantee that the two products can be used interchangeably, the assessment of population and individual bioequivalence is addressed through the application of a comprehensible three-step decision rule. An example study with a two-sequence four-period design is also analysed to illustrate the use of the proposed methods.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Vuorinen Jdoi
10.1002/(sici)1097-0258(19971015)16:19<2229::aid-ssubject
Has Abstractpub_date
1997-10-15 00:00:00pages
2229-43issue
19eissn
0277-6715issn
1097-0258pii
10.1002/(SICI)1097-0258(19971015)16:19<2229::AID-Sjournal_volume
16pub_type
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