# R: Data from the National Wilm's Tumor Study

nwtco {survival} | R Documentation

## Data from the National Wilm's Tumor Study

### Description

Missing data/masurement error example. Tumor histology predicts survival, but prediction is stronger with central lab histology than with the local institution determination.

### Usage

    nwtco

### Format

A data frame with 4028 observations on the following 9 variables.

`seqno`
  id number
`instit`
  Histology from local institution
`histol`
  Histology from central lab
`stage`
  Disease stage
`study`
  study
`rel`
  indicator for relapse
`edrel`
  time to relapse
`age`
  age in months
`in.subcohort`
  Included in the subcohort for the example in the paper

### Source

http://faculty.washington.edu/norm/software.html

### References

NE Breslow and N Chatterjee (1999), Design and analysis of two-phase studies with binary outcome applied to Wilms tumour prognosis. Applied Statistics 48, 457–68.

### Examples

    with(nwtco, table(instit,histol))
    anova(coxph(Surv(edrel,rel)~histol+instit,data=nwtco))
    anova(coxph(Surv(edrel,rel)~instit+histol,data=nwtco))

[Package survival version 2.32 Index]