PwrGSD v2.3.1


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Power in a Group Sequential Design

Tools for the evaluation of interim analysis plans for sequentially monitored trials on a survival endpoint; tools to construct efficacy and futility boundaries, for deriving power of a sequential design at a specified alternative, template for evaluating the performance of candidate plans at a set of time varying alternatives. See Izmirlian, G. (2014) <doi:10.4310/SII.2014.v7.n1.a4>.

Functions in PwrGSD

Name Description
Haybittle The Haybittle method of Boundary Construction
RR2RCM Relative risk to Relative Cumulative Mortality
Power Extract the Power results
Elements Create a subset of a "cpd.PwrGSD" object
PwrGSD Calculate Power in a Group Sequential Design
LanDemets The Lan-Demets method of Boundary Construction
CRRtoRR Cumulative-risk ratios to risk ratios
plot.cpd.PwrGSD Plot Method for cpd.PwrGSD objects
CDFOR2LRR Convert CDF Odds Ratio to Logged Relative Risks
CY2TOShaz Calender year rates to Study Year Rates
ObrienFleming The O'Brien-Fleming Alpha Spending Function
as.boundaries Convert a "PwrGSD" object to a "boundaries" object
RCM2RR Relative cumulative mortality to Relative Risk
lookup Lookup values for a piecewise constant function
GrpSeqBnds Computes efficacy and futility boundaries
Pow The Wang-Tsiatis Power Alpha Spending Function
SimGSB Verifies the results of "GrpSeqBnds" via simulation
wtdlogrank Weighted log-rank test
lung Mayo Clinic Lung Cancer Data
CondPower Conditional type I and type II error probabilities given current value of the test statistic
gsd.dens A function for computing the probability density for the group sequentially monitored test statistic.
DX A utility function for forming differences
EX1gXK A function for computing the bias adjusted point estimate for a statistic observed to cross the efficacy boundary.
IntSurvDiff Weighted Integrated Survival function test
agghaz Aggregated Hazard
paste The paste operator
SCtoBdry Converts a stochastic curtailment boundary (conditional type I or II error probability) into a (efficacy or futility) boundary on the standardized Z scale
cpd.PwrGSD Create a skeleton compound PwrGSD object
mysurvfit My Survfit
Pocock The Pocock Alpha Spending Function
SC The Stochastic Curtailment method of Boundary Construction
mystack Stack a dataset
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License GPL (>= 2)
NeedsCompilation yes
Packaged 2019-04-15 20:43:59 UTC; izmirlig
Repository CRAN
Date/Publication 2019-04-15 21:22:51 UTC
depends survival
Contributors Grant Izmirlian

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