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QT/Toxicology study with a Latin Square

  • 1.  QT/Toxicology study with a Latin Square

    Posted 04-16-2015 13:57
    This message has been cross posted to the following eGroups: Statistical Consulting Section and Biopharmaceutical Section .
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    A question for those with toxicology study expertise. 

    I was presented with the analysis results of a QT/QTc study in Cynologous "cyno" Monkeys .

    The design used a Latin square.  I've designed and analyzed Latin square studies in the past. 

    This study, had 4 treatments  and 3 active tx,and a placebo group, and four periods. 

     I also discovered, that the study had enrolled 4 (four) total animals, one animal per sequence. Its not clear from the report if these were randomly assigned. And within each period the animal was measured about 6 times .

    The analysis was then prepared with proc mixed (SAS). The mixed model had treatment, time and animal in the model. A number of large and statistically significant QT effects (treatment vs. placebo) were detected. 

    is this  "typical" for a QT/QTc  study in monkeys to have only one animal per sequence?  . 

     


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    Chris Barker, Ph.D.
    Consultant and
    Adjunct Associate Professor of Biostatistics
    www,barkerstats.com

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    "In composition you have all the time you want to decide what to say in 15 seconds, in improvisation you have 15 seconds."
    -Steve Lacy
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