APrioriPwr {SynergyLMM}R Documentation

A Priori Synergy Power Analysis Based on Variability and Drug Effect

Description

A priori power calculation for a hypothetical two-drugs combination study of synergy using linear-mixed models with varying drug combination effect and/or experimental variability.

Usage

APrioriPwr(
  npg = 5,
  time = c(0, 3, 5, 10),
  grwrControl = 0.08,
  grwrA = 0.07,
  grwrB = 0.06,
  grwrComb = 0.03,
  sd_ranef = 0.01,
  sgma = 0.1,
  sd_eval = NULL,
  sgma_eval = NULL,
  grwrComb_eval = NULL,
  method = "Bliss",
  ...
)

Arguments

npg

Number of subjects per group.

time

Vector with the times at which the tumor volume measurements have been performed.

grwrControl

Coefficient for Control treatment group tumor growth rate.

grwrA

Coefficient for Drug A treatment group tumor growth rate.

grwrB

Coefficient for Drug B treatment group tumor growth rate.

grwrComb

Coefficient for Combination (Drug A + Drug B) treatment group tumor growth rate.

sd_ranef

Random effects standard deviation (between-subject variance) for the model.

sgma

Residuals standard deviation (within-subject variance) for the model.

sd_eval

A vector with values representing the standard deviations of random effects, through which the power for synergy calculation will be evaluated.

sgma_eval

A vector with values representing the standard deviations of the residuals, through which the power for synergy calculation will be evaluated.

grwrComb_eval

A vector with values representing the coefficients for Combination treatment group tumor growth rate, through which the power for synergy calculation will be evaluated.

method

String indicating the method for synergy calculation. Possible methods are "Bliss" and "HSA", corresponding to Bliss and highest single agent, respectively.

...

Additional parameters to be passed to nlmeU::Pwr.lme method.

Details

APrioriPwr allows for total customization of an hypothetical drug combination study and allows the user to define several experimental parameters, such as the sample size, time of measurements, or drug effect, for the power evaluation of synergy for Bliss and HSA reference models. The power calculation is based on F-tests of the fixed effects of the model as previously described (Helms, R. W. (1992), Verbeke and Molenberghs (2009), Gałecki and Burzykowski (2013)).

The focus the power analysis with APrioriPwr is on the drug combination effect and the variability in the experiment. For other a priori power analysis see also PwrSampleSize() and PwrTime().

Value

The functions returns several plots:

The statistical power for the fitted model for the initial data set according to the values given by npg, time, grwrControl, grwrA, grwrB, grwrComb, sd_ranef and sgma is also shown in the console.

References

See Also

PostHocPwr,PwrSampleSize(), PwrTime().

Examples

APrioriPwr(
sd_eval = seq(0.01, 0.2, 0.01),
sgma_eval = seq(0.01, 0.2, 0.01),
grwrComb_eval = seq(0.01, 0.1, 0.005)
)


[Package SynergyLMM version 1.0.1 Index]