AnIntroductiontoStatisticsinEarlyPhaseTrialsAnIntroductiontoStatisticsinEarlyPhaseTrialsStevenA.Julious,SayBengTanandDavidMachin©2010JohnWiley&SonsLtdISBN:978-0-470-05985-2ANINTRODUCTIONTOSTATISTICSINEARLYPHASETRIALSSTEVENA.JULIOUSMedicalStatisticsGroup,SchoolofHealthandRelatedResearch,UniversityofSheffield,UKSAYBENGTANSingaporeClinicalResearchInstituteandDuke-NUSGraduateMedicalSchool,SingaporeDAVIDMACHINUniversityofLeicesterandUniversityofSheffield,UKAJohnWiley&Sons,Ltd.,PublicationThiseditionfirstpublished2010�2010JohnWiley&SonsLtdWiley-BlackwellisanimprintofJohnWiley&Sons,formedbythemergerofWiley’sglobalScientific,TechnicalandMedicalbusinesswithBlackwellPublishing.RegisteredofficeJohnWiley&SonsLtd,TheAtrium,SouthernGate,Chichester,WestSussex,PO198SQ,UKOtherEditorialOffices9600GarsingtonRoad,Oxford,OX42DQ,UK111RiverStreet,Hoboken,NJ07030-5774,USAFordetailsofourglobaleditorialoffices,forcustomerservicesandforinformationabouthowtoapplyforpermissiontoreusethecopyrightmaterialinthisbookpleaseseeourwebsiteatwww.wiley.com/wiley-blackwellTherightoftheauthortobeidentifiedastheauthorofthisworkhasbeenassertedinaccordancewiththeCopyright,DesignsandPatentsAct1988.Allrightsreserved.Nopartofthispublicationmaybereproduced,storedinaretrievalsystem,ortransmitted,inanyformorbyanymeans,electronic,mechanical,photocopying,recordingorotherwise,exceptaspermittedbytheUKCopyright,DesignsandPatentsAct1988,withoutthepriorpermissionofthepublisher.Wileyalsopublishesitsbooksinavarietyofelectronicformats.Somecontentthatappearsinprintmaynotbeavailableinelectronicbooks.Designationsusedbycompaniestodistinguishtheirproductsareoftenclaimedastrademarks.Allbrandnamesandproductnamesusedinthisbookaretradenames,servicemarks,trademarksorregisteredtrademarksoftheirrespectiveowners.Thepublisherisnotassociatedwithanyproductorvendormentionedinthisbook.Thispublicationisdesignedtoprovideaccurateandauthoritativeinformationinregardtothesubjectmattercovered.Itissoldontheunderstandingthatthepublisherisnotenga...