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Activity Number:
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369
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Type:
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Topic Contributed
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Date/Time:
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Wednesday, August 1, 2007 : 8:30 AM to 10:20 AM
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Sponsor:
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Biopharmaceutical Section
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| Abstract - #309647 |
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Title:
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Uniformly Balanced Repeated Measurements Designs in the Presence of Subject Dropout
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Author(s):
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Dibyen Majumdar*+
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Companies:
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University of Illinois at Chicago
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Address:
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MSCS mc249, Chicago, IL, 60607,
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Keywords:
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Crossover studies ; Optimal Designs ; Design Efficiency ; Connectedness
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Abstract:
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Uniformly balanced repeated measurements designs have been extensively studied in the literature. It has been shown that they possess elegant combinatorial properties. They are highly efficient crossover designs. In 1999, Low, Lewis and Prescott showed that a crossover design based on a Williams Latin square (which is a uniformly balanced repeated measurements design) of order 4 can suffer substantial loss of efficiency if some observations in the final period are unavailable. Indeed, if all observations are missing, the design becomes disconnected. In this talk we will examine some properties of these designs when there is a possibility that observations may be unavailable due to subject dropout. We also investigate designs with minimal loss of efficiency under subject dropout.
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