miceData: Lung Tumor Interval Censored Data from Hoel and Walburg 1972

In icenReg: Regression Models for Interval Censored Data

Description

RFM mice were sacrificed and examined for lung tumors. This resulted in current status interval censored data: if the tumor was present, this implied left censoring and if no tumor was present this implied right censoring. Mice were placed in two different groups: conventional environment or germ free environment.

Fields

l

left side of observation interval

u

right side of observation interval

grp

Group for mouse. Either ce (conventional environment) or ge (grem-free environment)

References

Hoel D. and Walburg, H.,(1972), Statistical analysis of survival experiments, The Annals of Statistics, 18, 1259-1294

Examples

data(miceData)
 
coxph_fit <- ic_sp(Surv(l, u, type = 'interval2') ~ grp, 
                    bs_samples = 50,	
                    data = miceData)
 
#In practice, more bootstrap samples should be used for inference
#Keeping it quick for CRAN testing purposes 
 
summary(coxph_fit)

Example output

Loading required package: survival
Loading required package: Rcpp
Loading required package: coda

Model:  Cox PH
Baseline:  semi-parametric 
Call: ic_sp(formula = Surv(l, u, type = "interval2") ~ grp, data = miceData, 
    bs_samples = 50)

      Estimate Exp(Est) Std.Error z-value       p
grpge   0.6785    1.971    0.3219   2.108 0.03505

final llk =  -76.56894 
Iterations =  54 
Bootstrap Samples =  50 
WARNING: only  50  bootstrap samples used for standard errors. 
Suggest using more bootstrap samples for inference

icenReg documentation built on Oct. 23, 2020, 8:11 p.m.