simKHCE: Simulate a kidney disease 'hce' dataset

View source: R/simKHCE.R

simKHCER Documentation

Simulate a kidney disease hce dataset

Description

Simulate a kidney disease hce dataset, capturing eGFR (Estimated Glomerular Filtration Rate) progression over time, along with a competing and dependent terminal event: KFRT (Kidney Failure Replacement Therapy)

Usage

simKHCE(
  n,
  CM_A,
  CM_P = -4,
  n0 = n,
  TTE_A = 10,
  TTE_P = TTE_A,
  fixedfy = 2,
  Emin = 20,
  Emax = 100,
  sigma = 8,
  Sigma = 3,
  m = 10,
  theta = -0.23,
  phi = 0
)

Arguments

n

sample size in the active treatment group.

CM_A

annualized eGFR slope in the active group.

CM_P

annualized eGFR slope in the control group.

n0

sample size in the control treatment group.

TTE_A

event rate per year in the active group for KFRT.

TTE_P

event rate per year in the placebo group for KFRT.

fixedfy

length of follow-up in years.

Emin

lower limit of eGFR at baseline.

Emax

upper limit of eGFR at baseline.

sigma

within-patient standard deviation.

Sigma

between-patient standard deviation.

m

number of equidistant visits.

theta

coefficient of dependence of eGFR values and the risk of KFRT.

phi

coefficient of proportionality (between 0 and 1) of the treatment effect. The case of 0 corresponds to the uniform treatment effect.

Details

The default setting is TTE_A = TTE_P because, conditional on eGFR level, the treatment effect does not influence the event rate of KFRT. In this model, the effect of treatment on KFRT operates entirely through its impact on eGFR decline.

The parameters TTE_A and theta are chosen so that when GFR is 10, the event rate is 1 per year, and when GFR is 30, the event rate is 0.01 per year. These parameter values are obtained by solving the equation rate0*exp(GFR*theta) = rate for rate0 and theta.

Value

a list containing the dataset GFR for longitudinal measurements of eGFR and the competing KFRT events, the dataset ADET for the time-to-event kidney outcomes (sustained declines or sustained low levels of eGFR), and the combined HCE dataset for the kidney hierarchical composite endpoint.

See Also

simHCE() for a general function of simulating hce datasets.

Examples

# Example 1
set.seed(2022)
L <- simKHCE(n = 1000, CM_A = -3.25)
dat <- L$HCE
calcWO(dat)

hce documentation built on Aug. 23, 2025, 1:11 a.m.